Space debris is becoming a major potential safety hazard for spacecraft in normal operation. Large space debris can be detected and identified by ground-based observation methods to guarantee the operation safety of the spacecraft. Space-based optical detection method is mainly used to detect small space debris with the size of 1~10 cm. According to small space debris, combing infrared and visible light detection modes, remote detection and identification processes for small space debris are realized. The design parameters of infrared detection optical systems are proposed through calculating. A background elimination method is proposed according to the angular velocity difference between stars in the background and space debris target. And the space debris is observed by narrow field of view visible light focus method to record and extract the corner features of nine different angles to identify targets. Value simulation and experimental demonstration show that the small space debris can be detected and identified by the proposed algorithm effectively.