diff --git a/src/butil/iobuf.cpp b/src/butil/iobuf.cpp
index f1f3d02347..5ad1356653 100644
--- a/src/butil/iobuf.cpp
+++ b/src/butil/iobuf.cpp
@@ -1869,7 +1869,7 @@ bool IOBufAsZeroCopyInputStream::Skip(int count) {
     return false;
 }
 
-google::protobuf::int64 IOBufAsZeroCopyInputStream::ByteCount() const {
+int64_t IOBufAsZeroCopyInputStream::ByteCount() const {
     return _byte_count;
 }
 
@@ -1990,7 +1990,7 @@ void IOBufAsZeroCopyOutputStream::BackUp(int count) {
     LOG_IF(FATAL, count != 0) << "BackUp an empty IOBuf";
 }
 
-google::protobuf::int64 IOBufAsZeroCopyOutputStream::ByteCount() const {
+int64_t IOBufAsZeroCopyOutputStream::ByteCount() const {
     return _byte_count;
 }
 
diff --git a/src/json2pb/zero_copy_stream_writer.h b/src/json2pb/zero_copy_stream_writer.h
index 53455cc8e6..6404211958 100644
--- a/src/json2pb/zero_copy_stream_writer.h
+++ b/src/json2pb/zero_copy_stream_writer.h
@@ -29,7 +29,7 @@
 //    // Interfaces of ZeroCopyOutputStream
 //    bool Next(void** data, int* size);
 //    void BackUp(int count);
-//    google::protobuf::int64 ByteCount() const;
+//    int64_t ByteCount() const;
 //
 //private:
 //    IOBuf* _buf;