Abstract: The invention relates to a baseball batting practice device having a support frame and a frame member mounted on the support frame. An electrical power source is provided for randomly starting and stopping the frame member during upward and downward movement in a strike zone on the support frame. A flexible ball support arm having one of its ends mounted on the frame member and having a ball attached to its other end, such that the arm and ball will rotate in a vertical plane when the ball is struck by a batter. A control box having an on-off switch for a light and a device for computing the time of a batter's swing from the time the light comes on and the time the ball is struck by a bat.