diff --git a/yt_dlp/extractor/mixch.py b/yt_dlp/extractor/mixch.py
index 64bddc6605..07f347e659 100644
--- a/yt_dlp/extractor/mixch.py
+++ b/yt_dlp/extractor/mixch.py
@@ -129,7 +129,7 @@ class MixchMovieIE(InfoExtractor):
             'title': '夏☀️\nムービーへのポイントは本イベントに加算されないので配信にてお願い致します🙇🏻\u200d♀️\n#TGCCAMPUS #ミス東大 #ミス東大2024 ',
             'ext': 'mp4',
             'uploader': 'ミス東大No.5 松藤百香🍑💫',
-            'uploader_id': 12299174,
+            'uploader_id': '12299174',
             'channel_follower_count': int,
             'view_count': int,
             'like_count': int,
@@ -159,7 +159,7 @@ class MixchMovieIE(InfoExtractor):
                 'title': ('movie', 'title', {str}),
                 'thumbnail': ('movie', 'thumbnailURL', {url_or_none}),
                 'uploader': ('ownerInfo', 'name', {str}),
-                'uploader_id': ('ownerInfo', 'id', {int_or_none}),
+                'uploader_id': ('ownerInfo', 'id', {int}, {str_or_none}),
                 'channel_follower_count': ('ownerInfo', 'fan', {int_or_none}),
                 'view_count': ('ownerInfo', 'view', {int_or_none}),
                 'like_count': ('movie', 'favCount', {int_or_none}),