diff --git a/net/FlatBuffers/ByteBuffer.cs b/net/FlatBuffers/ByteBuffer.cs
index 277fc1f82..1b2e1afe1 100644
--- a/net/FlatBuffers/ByteBuffer.cs
+++ b/net/FlatBuffers/ByteBuffer.cs
@@ -554,7 +554,7 @@ namespace FlatBuffers
             }
             else
             {
-                *(ulong*)(ptr + offset) = ReverseBytes(*(ulong*)(ptr + offset));
+                *(ulong*)(ptr + offset) = ReverseBytes(*(ulong*)(&value));
             }
         }
 #else // !UNSAFE_BYTEBUFFER