A surgical stapler comprising: a shaft extending along a longitudinal axis having a proximal end and a distal end, a first jaw and a second jaw extending from the distal end of the shaft, the second jaw defining a cartridge support arranged to receive a staple cartridge having a plurality of staples and movable towards the first jaw along the longitudinal axis; an actuator coupled to the proximal end of the shaft; a staple pusher (14, 15) coupled to the actuator and movable along the longitudinal axis to push the plurality of staples out of the cartridge along the longitudinal axis; the staple pusher (14, 15) comprising a distal portion of the staple pusher (14, 15) pivotally connected to a proximal portion of the staple pusher (14, 15), the distal portion pivotally biased by biasing means relative to the proximal portion; characterized in that: the stapler pusher (14, 15) further comprises an L-shaped slot formed on the distal portion of the staple pusher (14, 15), the L-shaped slot having a bottom portion; the cartridge support comprises a pin disposed on the cartridge support and extending through the L-shaped slot; the distal portion of the staple pusher (14, 15) being biased to engage the pin in the bottom portion of the L-shaped slot in order to prevent movement of the stapler pusher (14, 15) towards the first jaw without a loaded staple cartridge received in the second jaw; wherein the distal portion is configured such that when loading a filled staple cartridge in the second jaw, the filled staple cartridge engages the distal portion such as to move the bottom portion of the L-shaped slot out of contact with the pin, allowing unobstructed movement of the stapler pusher (14, 15). a shaft extending along a longitudinal axis having a proximal end and a distal end, a first jaw and a second jaw extending from the distal end of the shaft, the second jaw defining a cartridge support arranged to receive a staple cartridge having a plurality of staples and movable towards the first jaw along the longitudinal axis; an actuator coupled to the proximal end of the shaft; a staple pusher (14, 15) coupled to the actuator and movable along the longitudinal axis to push the plurality of staples out of the cartridge along the longitudinal axis; the staple pusher (14, 15) comprising a distal portion of the staple pusher (14, 15) pivotally connected to a proximal portion of the staple pusher (14, 15), the distal portion pivotally biased by biasing means relative to the proximal portion; characterized in that: the stapler pusher (14, 15) further comprises an L-shaped slot formed on the distal portion of the staple pusher (14, 15), the L-shaped slot having a bottom portion; the cartridge support comprises a pin disposed on the cartridge support and extending through the L-shaped slot; the distal portion of the staple pusher (14, 15) being biased to engage the pin in the bottom portion of the L-shaped slot in order to prevent movement of the stapler pusher (14, 15) towards the first jaw without a loaded staple cartridge received in the second jaw; wherein the distal portion is configured such that when loading a filled staple cartridge in the second jaw, the filled staple cartridge engages the distal portion such as to move the bottom portion of the L-shaped slot out of contact with the pin, allowing unobstructed movement of the stapler pusher (14, 15).