An endoscopic scissor instrument includes an elongate hollow member having a proximal end and a distal end, an actuator that moves axially through the hollow member, and first and second scissor blades with respective cutting surfaces. At least one of the first and second scissor blades are rotatably coupled to the hollow member adjacent its distal end. At least one of the first and second scissor blades includes a base supporting a resilient leaf-spring portion that includes a respective cutting edge. The resilient leaf-spring portion extends from the base in a cantilevered arrangement along the length of the leaf-spring portion. The cantilevered arrangement of said leaf-spring portion generates a spring force to maintain a consistent and continuous mating force between the two opposed sharpened cutting edges preferably over the complete range of rotational movement of the scissor blades.