diff --git a/src/main/kotlin/cn/tursom/core/buffer/ByteBuffer.kt b/src/main/kotlin/cn/tursom/core/buffer/ByteBuffer.kt
index b167a93..9ef08d1 100644
--- a/src/main/kotlin/cn/tursom/core/buffer/ByteBuffer.kt
+++ b/src/main/kotlin/cn/tursom/core/buffer/ByteBuffer.kt
@@ -98,7 +98,7 @@ interface ByteBuffer : Closeable {
 
   fun toString(size: Int): String {
     val bytes = getBytes(size)
-    readPosition -= bytes.size
+    readPosition += bytes.size
     return String(bytes)
   }