Most of the industrial controllers used today for 6 DOF robot arm utilize PID controllers. Using PID controller without tuning method leads to response with unsuitable time-domain specifications (maximum-overshot, settling-time, rise-time, …). Ziegler-Nichols method was introduced as the conventional method for tuning the PID controller. By using this method, the enhancement of the response time-domain specifications is not sufficient. Recently, fuzzy logic with and without PID-controller, and genetic algorithm with PID-controller are also introduced to obtain suitable time-domain specifications of the response. This paper will introduce a new comparative study for these four tuning methods applied on 6 DOF robot arm in view of the response time domain specifications and the steady state error. Simulation results are obtained using the Mat lap/Simulink. The results show that the Fuzzy with PID controller responds better than the others in case of change in load and system disturbances.