diff --git a/atst/forms/task_order.py b/atst/forms/task_order.py
index c8fcbdb9..30a86c3b 100644
--- a/atst/forms/task_order.py
+++ b/atst/forms/task_order.py
@@ -63,6 +63,7 @@ class CLINForm(FlaskForm):
 class AttachmentForm(BaseForm):
     filename = HiddenField(id="attachment_filename")
     object_name = HiddenField(id="attachment_object_name")
+    accept = ".pdf,application/pdf"
 
 
 class TaskOrderForm(BaseForm):