This paper describes the throwing motion control for the Pendubot which has an angular constraint. The controller is based on input-output linearization and output zeroing control. In the control method, the position of hand is to be controlled on a target pathway. The purpose of this paper is to oprimize the target pathway in order to maximize the speed of horizontal throw. This paper introduces Bezier curve as the target pathway to achieve this purpose. By using Bezier curve, is is able to throw accurately and set more flexible target pathway.