diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index ff46e08..7295845 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -8,6 +8,7 @@ ChangeLog
 -----
 - Exclude models.Aerich.
 - Add init record when init-db.
+- Fix version num str.
 
 0.1.6
 -----
diff --git a/aerich/migrate.py b/aerich/migrate.py
index 1b415e9..d859e02 100644
--- a/aerich/migrate.py
+++ b/aerich/migrate.py
@@ -80,7 +80,7 @@ class Migrate:
         if not last_version:
             return None
         version = last_version.version
-        return version.split("_")[0]
+        return int(version.split("_")[0])
 
     @classmethod
     async def generate_version(cls, name=None):