diff --git a/backend/Makefile b/backend/Makefile
index 039340c..41fe1a3 100644
--- a/backend/Makefile
+++ b/backend/Makefile
@@ -34,6 +34,7 @@ clean:
 	rm -f plantuml.jar
 	rm -f erd.png
 	rm -f config.toml
+	rm -f database.txt
 
 # Test target
 test: db.sqlite3