diff --git a/README.md b/README.md
index 97a5890..d8ba215 100644
--- a/README.md
+++ b/README.md
@@ -44,6 +44,10 @@ func main() {
 
 ## Release Note
 
+### v0.4.0(TBA)
+- **IMPORTANT** goimagehash does not have compatible with the before version
+when it comes to the serialization based on string. bit set order is changed.
+
 ### v0.3.0
 - Support DifferenceHashExtend.
 - Support AverageHashExtend.