diff --git a/.gitignore b/.gitignore
index 3e759b7..3af01dd 100644
--- a/.gitignore
+++ b/.gitignore
@@ -328,3 +328,5 @@ ASALocalRun/
 
 # MFractors (Xamarin productivity tool) working folder 
 .mfractor/
+
+!Common/Log/
diff --git a/Common/Log/LogLevel.cs b/Common/Log/LogLevel.cs
new file mode 100644
index 0000000..5d9344c
--- /dev/null
+++ b/Common/Log/LogLevel.cs
@@ -0,0 +1,19 @@
+namespace LeanCloud.Common {
+    /// <summary>
+    /// 日志级别
+    /// </summary>
+    public enum LogLevel {
+        /// <summary>
+        /// 调试级别
+        /// </summary>
+        Debug,
+        /// <summary>
+        /// 警告级别
+        /// </summary>
+        Warn,
+        /// <summary>
+        /// 错误级别
+        /// </summary>
+        Error,
+    }
+}
diff --git a/Common/Log/Logger.cs b/Common/Log/Logger.cs
new file mode 100644
index 0000000..4e499d5
--- /dev/null
+++ b/Common/Log/Logger.cs
@@ -0,0 +1,40 @@
+using System;
+
+namespace LeanCloud.Common {
+    /// <summary>
+    /// 日志类
+    /// </summary>
+    public static class Logger {
+        /// <summary>
+        /// 日志回调接口，方便开发者调试
+        /// </summary>
+        /// <value>The log delegate.</value>
+        public static Action<LogLevel, string> LogDelegate {
+            get; set;
+        }
+
+        public static void Debug(string log) {
+            LogDelegate?.Invoke(LogLevel.Debug, log);
+        }
+
+        public static void Debug(string format, params object[] args) {
+            LogDelegate?.Invoke(LogLevel.Debug, string.Format(format, args));
+        }
+
+        public static void Warn(string log) {
+            LogDelegate?.Invoke(LogLevel.Warn, log);
+        }
+
+        public static void Warn(string format, params object[] args) {
+            LogDelegate?.Invoke(LogLevel.Warn, string.Format(format, args));
+        }
+
+        public static void Error(string log) {
+            LogDelegate?.Invoke(LogLevel.Error, log);
+        }
+
+        public static void Error(string format, params object[] args) {
+            LogDelegate?.Invoke(LogLevel.Error, string.Format(format, args));
+        }
+    }
+}
diff --git a/Test/Common.Test/AppRouterTest.cs b/Test/Common.Test/AppRouterTest.cs
index acbc144..b037029 100644
--- a/Test/Common.Test/AppRouterTest.cs
+++ b/Test/Common.Test/AppRouterTest.cs
@@ -5,15 +5,15 @@ using LeanCloud.Common;
 
 namespace Common.Test {
     public class AppRouterTest {
-        static void Print(LeanCloud.LogLevel level, string info) {
+        static void Print(LogLevel level, string info) {
             switch (level) {
-                case LeanCloud.LogLevel.Debug:
+                case LogLevel.Debug:
                     TestContext.Out.WriteLine($"[DEBUG] {info}");
                     break;
-                case LeanCloud.LogLevel.Warn:
+                case LogLevel.Warn:
                     TestContext.Out.WriteLine($"[WARNING] {info}");
                     break;
-                case LeanCloud.LogLevel.Error:
+                case LogLevel.Error:
                     TestContext.Out.WriteLine($"[ERROR] {info}");
                     break;
                 default:
@@ -24,12 +24,12 @@ namespace Common.Test {
 
         [SetUp]
         public void SetUp() {
-            LeanCloud.Logger.LogDelegate += Print;
+            Logger.LogDelegate += Print;
         }
 
         [TearDown]
         public void TearDown() {
-            LeanCloud.Logger.LogDelegate -= Print;
+            Logger.LogDelegate -= Print;
         }
 
         [Test]
diff --git a/Test/Storage.Test/ACLTest.cs b/Test/Storage.Test/ACLTest.cs
index 826891d..eb13f66 100644
--- a/Test/Storage.Test/ACLTest.cs
+++ b/Test/Storage.Test/ACLTest.cs
@@ -1,6 +1,7 @@
 using NUnit.Framework;
 using System.Threading.Tasks;
 using LeanCloud.Storage;
+using LeanCloud.Common;
 
 namespace LeanCloud.Test {
     public class ACLTest {
diff --git a/Test/Storage.Test/CloudTest.cs b/Test/Storage.Test/CloudTest.cs
index fdf5856..e723fbf 100644
--- a/Test/Storage.Test/CloudTest.cs
+++ b/Test/Storage.Test/CloudTest.cs
@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Threading.Tasks;
 using System.Linq;
 using LeanCloud.Storage;
+using LeanCloud.Common;
 
 namespace LeanCloud.Test {
     public class CloudTest {
diff --git a/Test/Storage.Test/ExceptionTest.cs b/Test/Storage.Test/ExceptionTest.cs
index 4097e6f..2341cb5 100644
--- a/Test/Storage.Test/ExceptionTest.cs
+++ b/Test/Storage.Test/ExceptionTest.cs
@@ -1,5 +1,6 @@
 using NUnit.Framework;
 using LeanCloud.Storage;
+using LeanCloud.Common;
 
 namespace LeanCloud.Test {
     public class ExceptionTest {
diff --git a/Test/Storage.Test/FileTest.cs b/Test/Storage.Test/FileTest.cs
index 45916dc..187b7cb 100644
--- a/Test/Storage.Test/FileTest.cs
+++ b/Test/Storage.Test/FileTest.cs
@@ -3,6 +3,7 @@ using System;
 using System.Text;
 using System.Threading.Tasks;
 using LeanCloud.Storage;
+using LeanCloud.Common;
 
 namespace LeanCloud.Test {
     public class FileTest {
diff --git a/Test/Storage.Test/ObjectTest.cs b/Test/Storage.Test/ObjectTest.cs
index 17925f4..f94a39f 100644
--- a/Test/Storage.Test/ObjectTest.cs
+++ b/Test/Storage.Test/ObjectTest.cs
@@ -3,6 +3,7 @@ using System;
 using System.Threading.Tasks;
 using System.Collections.Generic;
 using LeanCloud.Storage;
+using LeanCloud.Common;
 
 namespace LeanCloud.Test {
     public class ObjectTest {
diff --git a/Test/Storage.Test/OperationTest.cs b/Test/Storage.Test/OperationTest.cs
index 51951bf..ececc97 100644
--- a/Test/Storage.Test/OperationTest.cs
+++ b/Test/Storage.Test/OperationTest.cs
@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Threading.Tasks;
 using LeanCloud.Storage;
+using LeanCloud.Common;
 
 namespace LeanCloud.Test {
     public class OperationTest {
diff --git a/Test/Storage.Test/QueryTest.cs b/Test/Storage.Test/QueryTest.cs
index 66dee5b..30c385a 100644
--- a/Test/Storage.Test/QueryTest.cs
+++ b/Test/Storage.Test/QueryTest.cs
@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Threading.Tasks;
 using LeanCloud.Storage;
+using LeanCloud.Common;
 
 namespace LeanCloud.Test {
     public class QueryTest {
diff --git a/Test/Storage.Test/RelationTest.cs b/Test/Storage.Test/RelationTest.cs
index 6ac0904..433802b 100644
--- a/Test/Storage.Test/RelationTest.cs
+++ b/Test/Storage.Test/RelationTest.cs
@@ -3,6 +3,7 @@ using System.Threading.Tasks;
 using System.Collections.Generic;
 using System.Linq;
 using LeanCloud.Storage;
+using LeanCloud.Common;
 
 namespace LeanCloud.Test {
     public class RelationTest {
diff --git a/Test/Storage.Test/RoleTest.cs b/Test/Storage.Test/RoleTest.cs
index ccabcef..f11da18 100644
--- a/Test/Storage.Test/RoleTest.cs
+++ b/Test/Storage.Test/RoleTest.cs
@@ -4,6 +4,7 @@ using System.Collections.Generic;
 using System.Threading.Tasks;
 using System.Linq;
 using LeanCloud.Storage;
+using LeanCloud.Common;
 
 namespace LeanCloud.Test {
     [TestFixture]
diff --git a/Test/Storage.Test/SubClassTest.cs b/Test/Storage.Test/SubClassTest.cs
index a98c05f..9e1c994 100644
--- a/Test/Storage.Test/SubClassTest.cs
+++ b/Test/Storage.Test/SubClassTest.cs
@@ -2,6 +2,7 @@
 using System.Threading.Tasks;
 using System.Collections.Generic;
 using LeanCloud.Storage;
+using LeanCloud.Common;
 
 namespace LeanCloud.Test {
     internal class Hello : LCObject {
diff --git a/Test/Storage.Test/UserTest.cs b/Test/Storage.Test/UserTest.cs
index 2af6dc3..83a64e4 100644
--- a/Test/Storage.Test/UserTest.cs
+++ b/Test/Storage.Test/UserTest.cs
@@ -3,6 +3,7 @@ using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
 using LeanCloud.Storage;
+using LeanCloud.Common;
 
 namespace LeanCloud.Test {
     public class UserTest {