Magnetorheological (MR) damper is a smart vibration damping instrument widely used in automobile suspension, bridge building and other fields. In order to make the MR damper control better in the semiactive system and avoid the vibration energy dissipation as heat energy, the functional integration of MR damper is important. In this paper, the working principle of traditional MR damper and its application in the vehicle suspension system was described. Combined with the methodology of functional integration, the structure, working principle and current research status of the functional integrated MR damper was also analyzed, including the selfsensing MR damper, selfpowered MR damper, selfsensing and selfpowered MR damper, etc. Meanwhile, the new functional integrated MR dampers proposed by our group were also expounded in detail. The relevant results can provide some guidance for the design and further engineering applications of functional integrated MR damper.