diff --git a/common/retry/retry_test.go b/common/retry/retry_test.go
new file mode 100644
index 00000000..afe8ae38
--- /dev/null
+++ b/common/retry/retry_test.go
@@ -0,0 +1,59 @@
+package retry
+
+import (
+	"errors"
+	"testing"
+	"time"
+
+	"github.com/v2ray/v2ray-core/testing/unit"
+)
+
+var (
+	TestError = errors.New("This is a fake error.")
+)
+
+func TestNoRetry(t *testing.T) {
+	assert := unit.Assert(t)
+
+	startTime := time.Now().Unix()
+	Timed(10, 100000).On(func() error {
+		return nil
+	})
+	endTime := time.Now().Unix()
+
+	assert.Int64(endTime - startTime).AtLeast(0)
+}
+
+func TestRetryOnce(t *testing.T) {
+	assert := unit.Assert(t)
+
+	startTime := time.Now()
+	called := 0
+	Timed(10, 1000).On(func() error {
+		if called == 0 {
+			called++
+			return TestError
+		}
+		return nil
+	})
+	duration := time.Since(startTime)
+
+	assert.Int64(int64(duration / time.Millisecond)).AtLeast(900)
+}
+
+func TestRetryMultiple(t *testing.T) {
+	assert := unit.Assert(t)
+
+	startTime := time.Now()
+	called := 0
+	Timed(10, 1000).On(func() error {
+		if called < 5 {
+			called++
+			return TestError
+		}
+		return nil
+	})
+	duration := time.Since(startTime)
+
+	assert.Int64(int64(duration / time.Millisecond)).AtLeast(4900)
+}