Abstract: Aim To describe the composition nature and potential engineering applications of electrorheological fluid (ERF) and to present some existing problems of current ERFs, and the ways of solving them. Methods According to Bingham plastic model, the properities of ERF are analyzed and it's potential applications presented. Results and Conclusion The key to electrorheological technology lies in the ER fluids themselves. The performances of the ER fluid directly affect the success of ER devices, so it is important to develop highly qualified ER fluids.