This paper presents a connection mechanism for autonomous self-assembly of segmented space mirrors. Using this connection mechanism, space mirrors can be autonomously captured, positioned, locked and adjusted. The purpose of assembling space mirrors on orbit is to overcome the limits of launch volume and mass and provide a feasibility for future extremely large space telescope in order to improve optical performance to function as monolithic mirrors. In this paper, first, the design details and operation principle of the connection mechanism are presented. Then, based on the initial capture conditions, a double-contact model is investigated. And simulated results of the dynamic and optical performance show that the proposed mechanism overcomes significant alignment errors and is considered suitable for space optical system.