Electronically controlled power steering (ECPS) device is one of the new power steering systems with improved stability in high-speed condition compared with the conventional ones. We propose a new ECPS system which uses magneto-rheological fluid (MRF) and can be added to the conventional power steering system without major modification. MRF, which is one type of the controllable fluids, changes its rheological characteristics from Newtonian fluid to that of Bingham fluid as magnetic field is applied. It has several advantages such as high strength, robustness to impurities and wide operational temperature range. In order to verify the feasibility of the developed ECPS systems we performed experiments based on PID control. The experimental results show feasibility of the proposed device while further study on improving the time response of the MR device is demanded necessary.