diff --git a/account/urls/user.py b/account/urls/user.py
index 1c3ad368..921faf69 100644
--- a/account/urls/user.py
+++ b/account/urls/user.py
@@ -1,9 +1,10 @@
 from django.conf.urls import url
 
 from ..views.user import (SSOAPI, AvatarUploadAPI, TwoFactorAuthAPI,
-                          UserInfoAPI, UserProfileAPI)
+                          UserNameAPI, UserInfoAPI, UserProfileAPI)
 
 urlpatterns = [
+    url(r"^username/?$", UserNameAPI.as_view(), name="user_name_api"),
     url(r"^user/(?P<username>\w+)/?$", UserInfoAPI.as_view(), name="user_info_api"),
     url(r"^profile/?$", UserProfileAPI.as_view(), name="user_profile_api"),
     url(r"^avatar/upload/?$", AvatarUploadAPI.as_view(), name="avatar_upload_api"),
diff --git a/account/views/user.py b/account/views/user.py
index d0b83930..0c0ea111 100644
--- a/account/views/user.py
+++ b/account/views/user.py
@@ -19,6 +19,24 @@ from ..serializers import (SSOSerializer, TwoFactorAuthCodeSerializer,
                            EditUserProfileSerializer, AvatarUploadForm)
 
 
+class UserNameAPI(APIView):
+    def get(self, request):
+        """
+        Return Username to valid login status
+        """
+        try:
+            user = User.objects.get(id=request.user.id)
+        except User.DoesNotExist:
+            return self.success({
+                "username": "User does not exist",
+                "isLogin": False
+            })
+        return self.success({
+            "username": user.username,
+            "isLogin": True
+        })
+
+
 class UserInfoAPI(APIView):
     # @login_required
     @method_decorator(ensure_csrf_cookie)
diff --git a/deploy/requirements.txt b/deploy/requirements.txt
index 3d8bf5ad..b843e277 100644
--- a/deploy/requirements.txt
+++ b/deploy/requirements.txt
@@ -11,3 +11,5 @@ celery
 Envelopes
 qrcode
 flake8-coding
+requests
+django-redis
diff --git a/oj/local_settings.py b/oj/local_settings.py
index a57437d5..f5212ff6 100644
--- a/oj/local_settings.py
+++ b/oj/local_settings.py
@@ -24,6 +24,13 @@ CACHES = {
         "OPTIONS": {
             "CLIENT_CLASS": "django_redis.client.DefaultClient",
         }
+    },
+    "Throttling": {
+        "BACKEND": "django_redis.cache.RedisCache",
+        "LOCATION": "redis://127.0.0.1:6379/3",
+        "OPTIONS": {
+            "CLIENT_CLASS": "django_redis.client.DefaultClient",
+        }
     }
 }
 
diff --git a/oj/settings.py b/oj/settings.py
index e7199d92..c33efe61 100644
--- a/oj/settings.py
+++ b/oj/settings.py
@@ -45,6 +45,7 @@ INSTALLED_APPS = (
     'problem',
     'contest',
     'utils',
+    'submission',
 
     'rest_framework',
 )
diff --git a/oj/urls.py b/oj/urls.py
index 79e6b038..1e79aab5 100644
--- a/oj/urls.py
+++ b/oj/urls.py
@@ -10,5 +10,6 @@ urlpatterns = [
     url(r"^api/", include("problem.urls.oj")),
     url(r"^api/admin/", include("problem.urls.admin")),
     url(r"^api/admin/", include("contest.urls.admin")),
-    url(r"^api/", include("contest.urls.oj"))
+    url(r"^api/", include("contest.urls.oj")),
+    url(r"^api/", include("submission.urls.oj")),
 ]
diff --git a/submission/__init__.py b/submission/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/submission/models.py b/submission/models.py
new file mode 100644
index 00000000..9c6d823e
--- /dev/null
+++ b/submission/models.py
@@ -0,0 +1,42 @@
+from django.db import models
+from jsonfield import JSONField
+
+from utils.models import RichTextField
+from utils.shortcuts import rand_str
+
+
+class JudgeStatus:
+    COMPILE_ERROR = -2
+    WRONG_ANSWER = -1
+    ACCEPTED = 0
+    CPU_TIME_LIMIT_EXCEEDED = 1
+    REAL_TIME_LIMIT_EXCEEDED = 2
+    MEMORY_LIMIT_EXCEEDED = 3
+    RUNTIME_ERROR = 4
+    SYSTEM_ERROR = 5
+    PENDING = 6
+    JUDGING = 7
+    PARTIALLY_ACCEPTED = 8
+
+
+class Submission(models.Model):
+    id = models.CharField(max_length=32, default=rand_str, primary_key=True, db_index=True)
+    contest_id = models.IntegerField(db_index=True, null=True)
+    problem_id = models.IntegerField(db_index=True)
+    created_time = models.DateTimeField(auto_now_add=True)
+    user_id = models.IntegerField(db_index=True)
+    code = RichTextField()
+    result = models.IntegerField(default=JudgeStatus.PENDING)
+    # 判题结果的详细信息
+    info = JSONField(default={})
+    language = models.CharField(max_length=20)
+    shared = models.BooleanField(default=False)
+    # 题目状态为 Accepted 时才会存储相关info
+    accepted_time = models.IntegerField(blank=True, null=True)
+    accepted_info = JSONField(default={})
+
+    class Meta:
+        db_table = "submission"
+
+    def __str__(self):
+        return self.id
diff --git a/submission/serializers.py b/submission/serializers.py
new file mode 100644
index 00000000..32fe1670
--- /dev/null
+++ b/submission/serializers.py
@@ -0,0 +1,8 @@
+from utils.api import serializers
+from judge.languages import language_names
+
+
+class CreateSubmissionSerializer(serializers.Serializer):
+    problem_id = serializers.IntegerField()
+    language = serializers.ChoiceField(choices=language_names)
+    code = serializers.CharField(max_length=20000)
diff --git a/submission/tasks.py b/submission/tasks.py
new file mode 100644
index 00000000..ea9d6c8f
--- /dev/null
+++ b/submission/tasks.py
@@ -0,0 +1,7 @@
+from celery import shared_task
+from judge.tasks import JudgeDispatcher
+
+
+@shared_task
+def _judge(submission_obj, problem_obj):
+    return JudgeDispatcher(submission_obj, problem_obj).judge()
diff --git a/submission/test.py b/submission/test.py
new file mode 100644
index 00000000..e69de29b
diff --git a/submission/urls/__init__.py b/submission/urls/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/submission/urls/admin.py b/submission/urls/admin.py
new file mode 100644
index 00000000..e69de29b
diff --git a/submission/urls/oj.py b/submission/urls/oj.py
new file mode 100644
index 00000000..9f54c055
--- /dev/null
+++ b/submission/urls/oj.py
@@ -0,0 +1,9 @@
+from django.conf.urls import url
+
+from ..views.oj import (SubmissionAPI, SubmissionListAPI)
+
+urlpatterns = [
+    url(r"^submission/?$", SubmissionAPI.as_view(), name="submissiob_api"),
+    url(r"^submissions/?$", SubmissionListAPI.as_view(), name="submission_list_api"),
+    url(r"^submissions/(?P<page>\d+)/?$", SubmissionListAPI.as_view(), name="submission_list_page_api"),
+]
diff --git a/submission/views/__init__.py b/submission/views/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/submission/views/admin.py b/submission/views/admin.py
new file mode 100644
index 00000000..e69de29b
diff --git a/submission/views/oj.py b/submission/views/oj.py
new file mode 100644
index 00000000..eb43575d
--- /dev/null
+++ b/submission/views/oj.py
@@ -0,0 +1,169 @@
+from django.core.paginator import Paginator
+from django_redis import get_redis_connection
+
+from account.decorators import login_required
+from account.models import AdminType, User
+from problem.models import Problem
+
+from utils.api import CSRFExemptAPIView
+from utils.api import APIView, validate_serializer
+from utils.shortcuts import build_query_string
+from utils.throttling import TokenBucket, BucketController
+
+from ..models import Submission
+from ..serializers import CreateSubmissionSerializer
+from ..tasks import _judge
+
+
+def _submit_code(response, user, problem_id, language, code):
+    controller = BucketController(user_id=user.id,
+                                  redis_conn=get_redis_connection("Throttling"),
+                                  default_capacity=30)
+    bucket = TokenBucket(fill_rate=10,
+                         capacity=20,
+                         last_capacity=controller.last_capacity,
+                         last_timestamp=controller.last_timestamp)
+    if bucket.consume():
+        controller.last_capacity -= 1
+    else:
+        return response.error("Please wait %d seconds" % int(bucket.expected_time() + 1))
+
+    try:
+        problem = Problem.objects.get(id=problem_id)
+    except Problem.DoesNotExist:
+        return response.error("Problem not exist")
+
+    submission = Submission.objects.create(user_id=user.id,
+                                           language=language,
+                                           code=code,
+                                           problem_id=problem.id)
+
+    try:
+        _judge.delay(submission, problem)
+    except Exception as e:
+        return response.error("Failed")
+
+    return response.success({"submission_id": submission.id})
+
+
+class SubmissionAPI(APIView):
+    @validate_serializer(CreateSubmissionSerializer)
+    # @login_required
+    def post(self, request):
+        data = request.data
+        return _submit_code(self, request.user, data["problem_id"], data["language"], data["code"])
+
+    @login_required
+    def get(self, request):
+        submission_id = request.GET.get("submission_id")
+        if not submission_id:
+            return self.error("Parameter error")
+        try:
+            submission = Submission.objects.get(id=submission_id, user_id=request.user.id)
+        except Submission.DoesNotExist:
+            return self.error("Submission not exist")
+
+        response_data = {"result": submission.result}
+        if submission.result == 0:
+            response_data["accepted_answer_time"] = submission.accepted_answer_time
+        return self.success(response_data)
+
+
+class MyProblemSubmissionListAPI(APIView):
+    """
+    用户单个题目的全部提交列表
+    """
+    def get(self, request):
+        problem_id = request.GET.get("problem_id")
+        try:
+            problem = Problem.objects.get(id=problem_id, visible=True)
+        except Problem.DoesNotExist:
+            return self.error("Problem not exist")
+
+        submissions = Submission.objects.filter(user_id=request.user.id, problem_id=problem.id,
+                                                contest_id__isnull=True). \
+            order_by("-created_time"). \
+            values("id", "result", "created_time", "accepted_time", "language")
+
+        return self.success({"submissions": submissions, "problem": problem})
+
+
+class SubmissionListAPI(APIView):
+    """
+    所有提交的列表
+    """
+    def get(self, request, **kwargs):
+        submission_filter = {"my": None, "user_id": None}
+        show_all = False
+        page = kwargs.get("page", 1)
+
+        user_id = request.GET.get("user_id")
+        if user_id and request.user.admin_type == AdminType.SUPER_ADMIN:
+            submission_filter["user_id"] = user_id
+            submissions = Submission.objects.filter(user_id=user_id, contest_id__isnull=True)
+        else:
+            show_all = True
+            if request.GET.get("my") == "true":
+                submission_filter["my"] = "true"
+                show_all = False
+            if show_all:
+                submissions = Submission.objects.filter(contest_id__isnull=True)
+            else:
+                submissions = Submission.objects.filter(user_id=request.user.id, contest_id__isnull=True)
+
+        submissions = submissions.values("id", "user_id", "problem_id", "result", "created_time",
+                                         "accepted_time", "language").order_by("-created_time")
+
+        language = request.GET.get("language")
+        if language:
+            submissions = submissions.filter(language=language)
+            submission_filter["language"] = language
+
+        result = request.GET.get("result")
+        if result:
+            # TODO： 转换为数字结果
+            submissions = submissions.filter(result=int(result))
+            submission_filter["result"] = result
+
+        paginator = Paginator(submissions, 20)
+        try:
+            submissions = paginator.page(int(page))
+        except Exception:
+            return self.error("Page not exist")
+
+        # Cache
+        cache_result = {"problem": {}, "user": {}}
+        for item in submissions:
+            problem_id = item["problem_id"]
+            if problem_id not in cache_result["problem"]:
+                problem = Problem.objects.get(id=problem_id)
+                cache_result["problem"][problem_id] = problem.title
+            item["title"] = cache_result["problem"][problem_id]
+
+            user_id = item["user_id"]
+            if user_id not in cache_result["user"]:
+                user = User.objects.get(id=user_id)
+                cache_result["user"][user_id] = user
+            item["user"] = cache_result["user"][user_id]
+
+            if item["user_id"] == request.user.id or request.user.admin_type == AdminType.SUPER_ADMIN:
+                item["show_link"] = True
+            else:
+                item["show_link"] = False
+
+            previous_page = next_page = None
+            try:
+                previous_page = submissions.previous_page_number()
+            except Exception:
+                pass
+            try:
+                next_page = submissions.next_page_number()
+            except Exception:
+                pass
+
+            return self.success({"submissions": submissions, "page": int(page),
+                                 "previous_page": previous_page, "next_page": next_page,
+                                 "start_id": int(page) * 20 - 20,
+                                 "query": build_query_string(submission_filter),
+                                 "submission_filter": submission_filter,
+                                 "show_all": show_all})
diff --git a/utils/shortcuts.py b/utils/shortcuts.py
index 9962ade6..a7fcd116 100644
--- a/utils/shortcuts.py
+++ b/utils/shortcuts.py
@@ -44,3 +44,17 @@ def rand_str(length=32, type="lower_hex"):
         return random.choice("123456789abcdef") + get_random_string(length - 1, allowed_chars="0123456789abcdef")
     else:
         return random.choice("123456789") + get_random_string(length - 1, allowed_chars="0123456789")
+
+
+def build_query_string(kv_data, ignore_none=True):
+    # {"a": 1, "b": "test"} -> "?a=1&b=test"
+    query_string = ""
+    for k, v in kv_data.iteritems():
+        if ignore_none is True and kv_data[k] is None:
+            continue
+        if query_string != "":
+            query_string += "&"
+        else:
+            query_string = "?"
+        query_string += (k + "=" + str(v))
+    return query_string
diff --git a/utils/throttling.py b/utils/throttling.py
new file mode 100644
index 00000000..c1fe8dce
--- /dev/null
+++ b/utils/throttling.py
@@ -0,0 +1,91 @@
+from __future__ import print_function
+import time
+
+
+class TokenBucket:
+    def __init__(self, fill_rate, capacity, last_capacity, last_timestamp):
+        self.capacity = float(capacity)
+        self._left_tokens = last_capacity
+        self.fill_rate = float(fill_rate)
+        self.timestamp = last_timestamp
+
+    def consume(self, tokens=1):
+        if tokens <= self.tokens:
+            self._left_tokens -= tokens
+            return True
+        return False
+
+    def expected_time(self, tokens=1):
+        _tokens = self.tokens
+        tokens = max(tokens, _tokens)
+        return (tokens - _tokens) / self.fill_rate * 60
+
+    @property
+    def tokens(self):
+        if self._left_tokens < self.capacity:
+            now = time.time()
+            delta = self.fill_rate * ((now - self.timestamp) / 60)
+            self._left_tokens = min(self.capacity, self._left_tokens + delta)
+            self.timestamp = now
+        return self._left_tokens
+
+
+class BucketController:
+    def __init__(self, user_id, redis_conn, default_capacity):
+        self.user_id = user_id
+        self.default_capacity = default_capacity
+        self.redis = redis_conn
+        self.key = "bucket_" + str(self.user_id)
+
+    @property
+    def last_capacity(self):
+        value = self.redis.hget(self.key, "last_capacity")
+        if value is None:
+            self.last_capacity = self.default_capacity
+            return self.default_capacity
+        return int(value)
+
+    @last_capacity.setter
+    def last_capacity(self, value):
+        self.redis.hset(self.key, "last_capacity", value)
+
+    @property
+    def last_timestamp(self):
+        value = self.redis.hget(self.key, "last_timestamp")
+        if value is None:
+            timestamp = int(time.time())
+            self.last_timestamp = timestamp
+            return timestamp
+        return int(value)
+
+    @last_timestamp.setter
+    def last_timestamp(self, value):
+        self.redis.hset(self.key, "last_timestamp", value)
+
+
+"""
+# # Token bucket, to limit submission rate
+# # Demo
+
+success = failure = 0
+current_user_id = 1
+token_bucket_default_capacity = 50
+token_bucket_fill_rate = 10
+for i in range(5000):
+    controller = BucketController(user_id=current_user_id,
+                                  redis_conn=redis.Redis(),
+                                  default_capacity=token_bucket_default_capacity)
+    bucket = TokenBucket(fill_rate=token_bucket_fill_rate,
+                         capacity=token_bucket_default_capacity,
+                         last_capacity=controller.last_capacity,
+                         last_timestamp=controller.last_timestamp)
+    time.sleep(0.05)
+    if bucket.consume():
+        success += 1
+        print(i, ": Accepted")
+        controller.last_capacity -= 1
+    else:
+        failure += 1
+        print(i, "Dropped, time left ", bucket.expected_time())
+print(success, failure)
+"""