diff --git a/requirements.txt b/requirements.txt
index 8e07d19..78eab1b 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,3 @@
 # /ComfyUI-Prompt-Formatter/requirements.txt
 
-PyYAML
\ No newline at end of file
+PyYAML>=5.1
\ No newline at end of file