diff --git a/src/Neo.Compiler.MSIL/MSIL/Conv_Multi.cs b/src/Neo.Compiler.MSIL/MSIL/Conv_Multi.cs
index 20c57d4c2..e7aba1b0f 100644
--- a/src/Neo.Compiler.MSIL/MSIL/Conv_Multi.cs
+++ b/src/Neo.Compiler.MSIL/MSIL/Conv_Multi.cs
@@ -654,6 +654,7 @@ private int _ConvertCall(OpCode src, NeoMethod to)
                 }
                 else if (src.tokenMethod == "System.Byte[] System.Numerics.BigInteger::ToByteArray()")
                 {
+                    _Convert1by1(VM.OpCode.CONVERT, src, to, new byte[] { 0x28 });
                     return 0;
                 }
                 else if (src.tokenMethod == "System.Void System.Numerics.BigInteger::.ctor(System.Byte[])")
diff --git a/src/Neo.SmartContract.Framework/Helper.cs b/src/Neo.SmartContract.Framework/Helper.cs
index e3630d53b..7d2810dec 100644
--- a/src/Neo.SmartContract.Framework/Helper.cs
+++ b/src/Neo.SmartContract.Framework/Helper.cs
@@ -20,48 +20,40 @@ public static class Helper
         /// <summary>
         /// Converts byte to byte[] considering the byte as a BigInteger (0x00 at the end)
         /// </summary>
-        [OpCode(OpCode.CONVERT, StackItemType_ByteArray)]
-        public extern static byte[] AsByteArray(this byte source);
+        [OpCode(OpCode.PUSH1)]
+        [OpCode(OpCode.LEFT)]
+        public extern static byte[] ToByteArray(this byte source);
 
         /// <summary>
         /// Converts sbyte to byte[].
         /// </summary>
         [OpCode(OpCode.CONVERT, StackItemType_ByteArray)]
-        public extern static byte[] AsByteArray(this sbyte source);
+        public extern static byte[] ToByteArray(this sbyte source);
 
         /// <summary>
         /// Converts sbyte[] to byte[].
         /// </summary>
         [OpCode(OpCode.CONVERT, StackItemType_ByteArray)]
-        public extern static byte[] AsByteArray(this sbyte[] source);
+        public extern static byte[] ToByteArray(this sbyte[] source);
 
         /// <summary>
         /// Converts byte[] to sbyte[].
         /// </summary>
         [OpCode(OpCode.CONVERT, StackItemType_ByteArray)]
-        public extern static sbyte[] AsSbyteArray(this byte[] source);
+        public extern static sbyte[] ToSbyteArray(this byte[] source);
 
         /// <summary>
         /// Converts byte[] to BigInteger. No guarantees are assumed regarding BigInteger working range.
         /// Examples: [0x0a] -> 10; [0x80] -> -128; [] -> 0; [0xff00] -> 255
         /// </summary>
         [OpCode(OpCode.CONVERT, StackItemType_Integer)]
-        public extern static BigInteger AsBigInteger(this byte[] source);
-
-
-
-        /// <summary>
-        /// Converts BigInteger to byte[]. No guarantees are assumed regarding BigInteger working range.
-        /// Examples: 10 -> [0x0a]; 10 -> [0x0a00]; -128 -> [0x80]; -128 -> [0x80ff]; 0 -> []; 0 -> [0x00]; 255 -> [0xff00]
-        /// </summary>
-        [OpCode(OpCode.CONVERT, StackItemType_ByteArray)]
-        public extern static byte[] AsByteArray(this BigInteger source);
+        public extern static BigInteger ToBigInteger(this byte[] source);
 
         /// <summary>
         /// Converts string to byte[]. Examples: "hello" -> [0x68656c6c6f]; "" -> []; "Neo" -> [0x4e656f]
         /// </summary>
         [OpCode(OpCode.CONVERT, StackItemType_ByteArray)]
-        public extern static byte[] AsByteArray(this string source);
+        public extern static byte[] ToByteArray(this string source);
 
         /// <summary>
         /// Converts byte[] to string. Examples: [0x68656c6c6f] -> "hello"; [] -> ""; [0x4e656f] -> "Neo"
@@ -135,13 +127,6 @@ public static class Helper
         //    return (byte) source;
         //}
 
-        /// <summary>
-        /// Converts byte to byte[].
-        /// </summary>
-        [OpCode(OpCode.PUSH1)]
-        [OpCode(OpCode.LEFT)]
-        public extern static byte[] ToByteArray(this byte source);
-
         /// <summary>
         /// Converts parameter to sbyte from (big)integer range -128-255; faults if out-of-range.
         /// Examples: 256 -> fault; -1 -> -1 [0xff]; 255 -> -1 [0xff]; 0 -> 0 [0x00]; 10 -> 10 [0x0a]; 127 -> 127 [0x7f]; 128 -> -128 [0x80]
diff --git a/src/Neo.SmartContract.Framework/Services/Neo/Helper.cs b/src/Neo.SmartContract.Framework/Services/Neo/Helper.cs
index 18b2a9d2b..f956e53ec 100644
--- a/src/Neo.SmartContract.Framework/Services/Neo/Helper.cs
+++ b/src/Neo.SmartContract.Framework/Services/Neo/Helper.cs
@@ -9,7 +9,7 @@ public static StorageMap CreateMap(this StorageContext context, string prefix)
             return new StorageMap
             {
                 Context = context,
-                Prefix = prefix.AsByteArray()
+                Prefix = prefix.ToByteArray()
             };
         }
 
@@ -39,7 +39,7 @@ public static void Delete(this StorageMap map, byte[] key)
 
         public static void Delete(this StorageMap map, string key)
         {
-            byte[] k = map.Prefix.Concat(key.AsByteArray());
+            byte[] k = map.Prefix.Concat(key.ToByteArray());
             Storage.Delete(map.Context, k);
         }
 
@@ -51,7 +51,7 @@ public static byte[] Get(this StorageMap map, byte[] key)
 
         public static byte[] Get(this StorageMap map, string key)
         {
-            byte[] k = map.Prefix.Concat(key.AsByteArray());
+            byte[] k = map.Prefix.Concat(key.ToByteArray());
             return Storage.Get(map.Context, k);
         }
 
@@ -75,19 +75,19 @@ public static void Put(this StorageMap map, byte[] key, string value)
 
         public static void Put(this StorageMap map, string key, byte[] value)
         {
-            byte[] k = map.Prefix.Concat(key.AsByteArray());
+            byte[] k = map.Prefix.Concat(key.ToByteArray());
             Storage.Put(map.Context, k, value);
         }
 
         public static void Put(this StorageMap map, string key, BigInteger value)
         {
-            byte[] k = map.Prefix.Concat(key.AsByteArray());
+            byte[] k = map.Prefix.Concat(key.ToByteArray());
             Storage.Put(map.Context, k, value);
         }
 
         public static void Put(this StorageMap map, string key, string value)
         {
-            byte[] k = map.Prefix.Concat(key.AsByteArray());
+            byte[] k = map.Prefix.Concat(key.ToByteArray());
             Storage.Put(map.Context, k, value);
         }
     }
diff --git a/tests/Neo.Compiler.MSIL.UnitTests/TestClasses/Contract_NULL.cs b/tests/Neo.Compiler.MSIL.UnitTests/TestClasses/Contract_NULL.cs
index ec5cc34dd..3c4077bd0 100644
--- a/tests/Neo.Compiler.MSIL.UnitTests/TestClasses/Contract_NULL.cs
+++ b/tests/Neo.Compiler.MSIL.UnitTests/TestClasses/Contract_NULL.cs
@@ -54,13 +54,13 @@ public static bool IfNull(object obj)
 
         public static object NullCollationAndCollation(string code)
         {
-            return Storage.Get(code)?.AsBigInteger() ?? 123;
+            return Storage.Get(code)?.ToBigInteger() ?? 123;
         }
 
         public static object NullCollationAndCollation2(string code)
         {
             Storage.Put(code, "111");
-            return Storage.Get(code)?.AsBigInteger() ?? 123;
+            return Storage.Get(code)?.ToBigInteger() ?? 123;
         }
     }
 }
diff --git a/tests/Neo.Compiler.MSIL.UnitTests/TestClasses/Contract_TypeConvert.cs b/tests/Neo.Compiler.MSIL.UnitTests/TestClasses/Contract_TypeConvert.cs
index b7ffcc35e..a40985587 100644
--- a/tests/Neo.Compiler.MSIL.UnitTests/TestClasses/Contract_TypeConvert.cs
+++ b/tests/Neo.Compiler.MSIL.UnitTests/TestClasses/Contract_TypeConvert.cs
@@ -11,15 +11,15 @@ class Contract_TypeConvert : SmartContract.Framework.SmartContract
         public static object testType()
         {
             BigInteger int0 = 0;
-            var bts0 = int0.AsByteArray();
+            var bts0 = int0.ToByteArray();
             BigInteger int1 = 2;
-            var bts1 = int1.AsByteArray();
+            var bts1 = int1.ToByteArray();
 
             var bts2=new byte[1] { 3 };
-            var int2 = bts2.AsBigInteger();
+            var int2 = bts2.ToBigInteger();
 
             var bts3 = new byte[0];
-            var int3 = bts3.AsBigInteger();
+            var int3 = bts3.ToBigInteger();
 
             var arrobj = new object[8];
             arrobj[0] = int0;