The compound helicopter can vertically take-off, hover and conduct low speed flights. At the same time, it has high speed, long range and endurance. These features make it significant in both military and civilian fields. This paper concludes the advantages of compound helicopter compared with the traditional configuration, and gives an overview on the developing compound products nowadays. The overall configuration and aerodynamics interference are analyzed in detail, along with the control strategy and control/stability characteristic concluded. What’s more this work analyzes the multiple choices of rotor blade configuration and the assistant trust/lift system, and summarizes the technology features of the compound helicopter.