Percussion drilling is considered to be an efficient method to promote the rate of penetration among the numerous tools. Therefore, a vibration assisted rotary percussion drilling tool is presented in this paper, which is driven through the motion of drill string. Three simplified models of designed structures are compared in this paper to define which one is to the most appropriate. Results indicated the structure of model 3 presented the best performance, and that the static and amplitude of the load is dependent on the flow rate and outlet size, the amplitude of dynamic load increased by increasing of the frequency and the displacement.