diff --git a/src/Neo/SmartContract/JsonSerializer.cs b/src/Neo/SmartContract/JsonSerializer.cs
index 8390acd7d2..e9343456fb 100644
--- a/src/Neo/SmartContract/JsonSerializer.cs
+++ b/src/Neo/SmartContract/JsonSerializer.cs
@@ -36,6 +36,7 @@ public static class JsonSerializer
         /// </summary>
         /// <param name="item">The <see cref="StackItem"/> to serialize.</param>
         /// <returns>The serialized object.</returns>
+        [Obsolete("This method will be removed in the future, do not use.")]
         public static JToken Serialize(StackItem item)
         {
             switch (item)
diff --git a/tests/Neo.UnitTests/SmartContract/UT_JsonSerializer.cs b/tests/Neo.UnitTests/SmartContract/UT_JsonSerializer.cs
index 9b5b0c02a3..2e2e98e4f0 100644
--- a/tests/Neo.UnitTests/SmartContract/UT_JsonSerializer.cs
+++ b/tests/Neo.UnitTests/SmartContract/UT_JsonSerializer.cs
@@ -72,17 +72,6 @@ public void JsonTest_Array()
             Assert.AreEqual("[1,\"a==\",-1.3,null]", parsed.ToString());
         }
 
-        [TestMethod]
-        public void JsonTest_Serialize_Map_Test()
-        {
-            var entry = new Map
-            {
-                [new byte[] { 0xC1 }] = 1,
-                [new byte[] { 0xC2 }] = 2,
-            };
-            Assert.ThrowsExactly<DecoderFallbackException>(() => _ = JsonSerializer.Serialize(entry));
-        }
-
         [TestMethod]
         public void JsonTest_Bool()
         {
@@ -210,34 +199,6 @@ public void Deserialize_WrongJson()
             Assert.ThrowsExactly<FormatException>(() => _ = JsonSerializer.Deserialize(engine, JObject.Parse("x"), ExecutionEngineLimits.Default));
         }
 
-        [TestMethod]
-        public void Serialize_WrongJson()
-        {
-            Assert.ThrowsExactly<FormatException>(() => _ = JsonSerializer.Serialize(StackItem.FromInterface(new object())));
-        }
-
-        [TestMethod]
-        public void Serialize_EmptyObject()
-        {
-            var entry = new Map();
-            var json = JsonSerializer.Serialize(entry).ToString();
-
-            Assert.AreEqual("{}", json);
-        }
-
-        [TestMethod]
-        public void Serialize_Number()
-        {
-            var entry = new Array { 1, 9007199254740992 };
-            Assert.ThrowsExactly<InvalidOperationException>(() => _ = JsonSerializer.Serialize(entry));
-        }
-
-        [TestMethod]
-        public void Serialize_Null()
-        {
-            Assert.AreEqual(JObject.Null, JsonSerializer.Serialize(StackItem.Null));
-        }
-
         [TestMethod]
         public void Deserialize_EmptyObject()
         {
@@ -249,15 +210,6 @@ public void Deserialize_EmptyObject()
             Assert.IsEmpty((Map)items);
         }
 
-        [TestMethod]
-        public void Serialize_EmptyArray()
-        {
-            var entry = new Array();
-            var json = JsonSerializer.Serialize(entry).ToString();
-
-            Assert.AreEqual("[]", json);
-        }
-
         [TestMethod]
         public void Deserialize_EmptyArray()
         {
@@ -269,21 +221,6 @@ public void Deserialize_EmptyArray()
             Assert.IsEmpty((Array)items);
         }
 
-        [TestMethod]
-        public void Serialize_Map_Test()
-        {
-            var entry = new Map
-            {
-                ["test1"] = 1,
-                ["test3"] = 3,
-                ["test2"] = 2
-            };
-
-            var json = JsonSerializer.Serialize(entry).ToString();
-
-            Assert.AreEqual("{\"test1\":1,\"test3\":3,\"test2\":2}", json);
-        }
-
         [TestMethod]
         public void Deserialize_Map_Test()
         {
@@ -305,16 +242,6 @@ public void Deserialize_Map_Test()
             CollectionAssert.AreEqual(map.Values.Select(u => u.GetInteger()).ToArray(), new BigInteger[] { 123, 321 });
         }
 
-        [TestMethod]
-        public void Serialize_Array_Bool_Str_Num()
-        {
-            var entry = new Array { true, "test", 123 };
-
-            var json = JsonSerializer.Serialize(entry).ToString();
-
-            Assert.AreEqual("[true,\"test\",123]", json);
-        }
-
         [TestMethod]
         public void Deserialize_Array_Bool_Str_Num()
         {
@@ -333,20 +260,6 @@ public void Deserialize_Array_Bool_Str_Num()
             Assert.AreEqual(array[3].GetInteger(), BigInteger.Parse("90500000000000000000000000000"));
         }
 
-        [TestMethod]
-        public void Serialize_Array_OfArray()
-        {
-            var entry = new Array
-            {
-                new Array { true, "test1", 123 },
-                new Array { true, "test2", 321 }
-            };
-
-            var json = JsonSerializer.Serialize(entry).ToString();
-
-            Assert.AreEqual("[[true,\"test1\",123],[true,\"test2\",321]]", json);
-        }
-
         [TestMethod]
         public void Deserialize_Array_OfArray()
         {