diff --git a/bdchain/api/ac_chain.proto b/bdchain/api/ac_chain.proto
index 2081a32..e965743 100644
--- a/bdchain/api/ac_chain.proto
+++ b/bdchain/api/ac_chain.proto
@@ -13,7 +13,7 @@ service AccountingChain {
     rpc BlockNumber (BlockNumberRequest) returns (BlockNumberResponse);
     rpc GetBlockByNumber (GetBlockByNumberRequest) returns (Block);
     rpc GetBlockByHash (GetBlockByHashRequest) returns (Block);
-    rpc GetTransactionByHash (GetTransactionByHashRequest) returns (Block);
+    rpc GetTransactionByHash (GetTransactionByHashRequest) returns (Transaction);
     rpc GetTransactionByBlockNumberAndIndex (GetTransactionByBlockNumberAndIndexRequest) returns (Transaction);
     rpc GetTransactionByBlockHashAndIndex (GetTransactionByBlockHashAndIndexRequest) returns (Transaction);
 }