Abstract: A stapler includes a press handle, a loading arm for filling a staple stick having a side window thereon, an anvil base and a magazine prefilled with several sticks of staples engaged with the side window of the arm and having an angled spring plate normally braking a staple stick, whereby upon the retraction of a pusher in the arm, the angled spring plate in the magazine will be straightened to release a standby staple stick tensioned by a leaf spring in the magazine to be filled into the loading arm for convenient refilling of staples without uncovering the loading arm.