A series of factors existed in the environment of spacecrafts, which would affect the performance of spacecraft. However, the atomic oxygen is critical to the completion of missions. Therefore, to conduct scientific measurement of atomic oxygen and atmospheric density, a space environment detection system is comprehensively developed. The overall design is demonstrated in this paper. In addition, FPGA is used as control chip to collect atmospheric density and atomic oxygen flux. Through CAN bus, the system can communicate with data processing unit to realize real-time refresh of collected data. The system can provide effective data support for satellite to achieve intelligent orbit maintenance and technical support for safe operation of spacecraft.