diff --git a/src/main/kotlin/cn/tursom/core/buffer/ByteBuffer.kt b/src/main/kotlin/cn/tursom/core/buffer/ByteBuffer.kt
index 905d82b..c58ac0f 100644
--- a/src/main/kotlin/cn/tursom/core/buffer/ByteBuffer.kt
+++ b/src/main/kotlin/cn/tursom/core/buffer/ByteBuffer.kt
@@ -99,7 +99,7 @@ interface ByteBuffer : Closeable {
 
   fun toString(size: Int): String {
     val bytes = getBytes(size)
-    readPosition -= bytes.size
+    readPosition += bytes.size
     return String(bytes)
   }