Abstract: A ball throwing machine for tossing a plurality of balls in succession, one at a time. The machine has a frame adapted to rest on a supporting surface, a spring-loaded pivotally mounted catapult arm that receives, holds, and tosses the balls, and a cam wheel and cam wheel shaft turnably mounting the cam wheel on the frame. The shaft has an axis which is laterally offset from the pivot axis of the catapult arm. The cam wheel has peripheral teeth, and a power driven pinion engages the teeth to impart turning movement to the wheel. There are cam rollers on the wheel which engage, one at a time, a cam plate on the catapult arm. The arrangement is such that the catapult arm is periodically shifted toward a ball-receiving position, picks up a ball, and as the cam wheel turns further, one cam roller by-passes the cam plate enabling the catapult arm to snap under the action of the spring and toss the ball.