diff --git a/common/serial/bytes_test.go b/common/serial/bytes_test.go
index 4b37a42e..a873395c 100644
--- a/common/serial/bytes_test.go
+++ b/common/serial/bytes_test.go
@@ -24,3 +24,12 @@ func TestBytesToHex(t *testing.T) {
 		assert.String(test.output).Equals(BytesToHexString(test.input))
 	}
 }
+
+func TestInt64(t *testing.T) {
+	assert := assert.On(t)
+
+	x := int64(375134875348)
+	b := Int64ToBytes(x, []byte{})
+	v := BytesToInt64(b)
+	assert.Int64(x).Equals(v)
+}
diff --git a/common/serial/string_test.go b/common/serial/string_test.go
new file mode 100644
index 00000000..9464df5b
--- /dev/null
+++ b/common/serial/string_test.go
@@ -0,0 +1,20 @@
+package serial_test
+
+import (
+	"testing"
+
+	"v2ray.com/core/common"
+	"v2ray.com/core/common/buf"
+	. "v2ray.com/core/common/serial"
+	"v2ray.com/core/testing/assert"
+)
+
+func TestUint32(t *testing.T) {
+	assert := assert.On(t)
+
+	x := uint32(458634234)
+	s1 := Uint32ToBytes(x, []byte{})
+	s2 := buf.New()
+	common.Must(s2.AppendSupplier(WriteUint32(x)))
+	assert.Bytes(s1).Equals(s2.Bytes())
+}