diff --git a/rag/app/one.py b/rag/app/one.py
index 88ca9e376..fe648c71b 100644
--- a/rag/app/one.py
+++ b/rag/app/one.py
@@ -80,7 +80,7 @@ def chunk(filename, binary=None, from_page=0, to_page=100000,
         excel_parser = ExcelParser()
         sections = excel_parser.html(binary, 1000000000)
 
-    elif re.search(r"\.txt$", filename, re.IGNORECASE):
+    elif re.search(r"\.(txt|md|markdown)$", filename, re.IGNORECASE):
         callback(0.1, "Start to parse.")
         txt = ""
         if binary: