diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 00000000..7302df18
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,5 @@
+# Changelog
+
+## latest
+IMPROVEMENTS
+* [\#53](https://github.com/binance-chain/go-sdk/pull/53) [SOURCE] change the default source into 0
\ No newline at end of file
diff --git a/types/config.go b/types/config.go
index eff891e8..b973b7d2 100644
--- a/types/config.go
+++ b/types/config.go
@@ -6,6 +6,4 @@ const (
 	DefaultAPIVersionPrefix = "/api/v1"
 	DefaultWSPrefix         = "/api/ws"
 	NativeSymbol            = "BNB"
-
-	GoSdkSource = 2
 )
diff --git a/types/tx/stdtx.go b/types/tx/stdtx.go
index fb60ee1c..6c577f60 100644
--- a/types/tx/stdtx.go
+++ b/types/tx/stdtx.go
@@ -6,7 +6,7 @@ import (
 	"github.com/tendermint/tendermint/libs/common"
 )
 
-const Source int64 = 2
+const Source int64 = 0
 
 type Tx interface {