This paper presents a design of tuning mechanism of Proportional Integral Derivative Controller for application in three phase induction motor speed controls. It demonstrates, in detail, how to employ the MatLab tool so as to search efficiently for the optimal PID controller parameters within a mechanism system. The proposed approach has superior features, including: easy implementation; stable convergence characteristics; and less computational effort. Three phase induction motors has complex mathematical modelling which makes it difficult to design the speed controller. Software PID Tuning Mechanismwas developed herein and used to obtain both the initial PID parameters under normal operating conditions and the optimal parameters of PID control under fully-loaded conditions. The proposed PID controller Tuning Mechanism will automatically tune its parameters within these ranges. In order to prove the performance of the proposed tuning mechanism for the PID controller, a three phase asynchronous motor was modelled in MATLAB, the transfer function was obtained using the software and a controller was designed using PID. The modelling and simulations results show the potential of the proposed controller to be very efficient.