diff --git a/seahub/settings.py b/seahub/settings.py
index a9ee7c8e60..6c21614d9c 100644
--- a/seahub/settings.py
+++ b/seahub/settings.py
@@ -423,7 +423,7 @@ FILE_ENCODING_LIST = ['auto', 'utf-8', 'gbk', 'ISO-8859-1', 'ISO-8859-5']
 FILE_ENCODING_TRY_LIST = ['utf-8', 'gbk']
 HIGHLIGHT_KEYWORD = False # If True, highlight the keywords in the file when the visit is via clicking a link in 'search result' page.
 # extensions of previewed files
-TEXT_PREVIEW_EXT = """ac, am, bat, c, cc, cmake, cpp, cs, css, diff, el, h, html, htm, java, js, json, less, make, org, php, pl, properties, py, rb, scala, script, sh, sql, txt, text, tex, vi, vim, xhtml, xml, log, csv, groovy, rst, patch, go"""
+TEXT_PREVIEW_EXT = """ac, am, bat, c, cc, cmake, cpp, cs, css, diff, el, h, html, htm, java, js, json, less, make, org, php, pl, properties, py, rb, scala, script, sh, sql, txt, text, tex, vi, vim, xhtml, xml, log, csv, groovy, rst, patch, go, yml"""
 
 # Common settings(file extension, storage) for avatar and group avatar.
 AVATAR_FILE_STORAGE = '' # Replace with 'seahub.base.database_storage.DatabaseStorage' if save avatar files to database