Abstract：Reuse is a promising technology for launch vehicles. Rocket based combined cycle(RBCC) propulsion system is a good choice for reusable launch vehicles. In this article the development status of RBCC engine and key technological issues are described, possible application areas, and development path are analyzed as well. To make full use of the advantages of ramjet and rocket engine and remedy function disfigurement and performance deficiency of LRE(改为全称) or ramjet distinguishes RBCC engine from other power engines. On the basis of current technologies, the RBCC engine solution formed by different working modals and engine configurations is the developmental route of RBCC power system to meet the needs of fly mission.