diff --git a/beets/util/__init__.py b/beets/util/__init__.py
index 01bd452bc..472f693b6 100644
--- a/beets/util/__init__.py
+++ b/beets/util/__init__.py
@@ -267,7 +267,8 @@ def prune_dirs(path, root=None, clutter=('.DS_Store', 'Thumbs.db')):
             # Directory gone already.
             continue
         clutter = [bytestring_path(c) for c in clutter]
-        if fnmatch_all(os.listdir(directory), clutter):
+        match_paths = [bytestring_path(d) for d in os.listdir(directory)]
+        if fnmatch_all(match_paths, clutter):
             # Directory contains only clutter (or nothing).
             try:
                 shutil.rmtree(directory)