diff --git a/src/neoxp/Extensions/Extensions.cs b/src/neoxp/Extensions/Extensions.cs
index 3df9836e..be0cbd69 100644
--- a/src/neoxp/Extensions/Extensions.cs
+++ b/src/neoxp/Extensions/Extensions.cs
@@ -119,6 +119,33 @@ public static bool TryGetBytesFromBase64String(this string text, out Span<byte>
 
 
 
+
+        public static string EscapeString(this string text)
+        {
+            if (text.Any(IsInvisibleChar))
+            {
+                var sb = new StringBuilder();
+                foreach (var c in text)
+                {
+                    if (c.IsInvisibleChar())
+                    {
+                        sb.Append($"\\u{(int)c:x4}");
+                    }
+                    else
+                    {
+                        sb.Append(c);
+                    }
+                }
+                return sb.ToString();
+            }
+            return text;
+        }
+
+        public static bool IsInvisibleChar(this char c)
+        {
+            return char.IsControl(c) || char.IsHighSurrogate(c) || char.IsLowSurrogate(c);
+        }
+
         public static void WriteJson(this Newtonsoft.Json.JsonWriter writer, Neo.Json.JToken? json)
         {
             switch (json)
diff --git a/src/neoxp/TransactionExecutor.cs b/src/neoxp/TransactionExecutor.cs
index 1afeffc7..776a1027 100644
--- a/src/neoxp/TransactionExecutor.cs
+++ b/src/neoxp/TransactionExecutor.cs
@@ -294,7 +294,7 @@ static async Task WriteStackItemAsync(System.IO.TextWriter writer, Neo.VM.Types.
                     case Neo.VM.Types.ByteString byteString:
                         if (byteString.GetSpan().TryGetUtf8String(out var text))
                         {
-                            await WriteLineAsync($"{Neo.Helper.ToHexString(byteString.GetSpan())}({text})").ConfigureAwait(false);
+                            await WriteLineAsync($"{Neo.Helper.ToHexString(byteString.GetSpan())}({text.EscapeString()})").ConfigureAwait(false);
                         }
                         else
                         {