diff --git a/tonic/datasets/nmnist.py b/tonic/datasets/nmnist.py
index 9d97daa..3e4fab0 100644
--- a/tonic/datasets/nmnist.py
+++ b/tonic/datasets/nmnist.py
@@ -97,6 +97,7 @@ def __init__(
 
         file_path = os.path.join(self.location_on_system, self.folder_name)
         for path, dirs, files in os.walk(file_path):
+            dirs.sort()
             files.sort()
             for file in files:
                 if file.endswith("bin"):