At present, there is limited literature on the application of fiber optic rotary joint（FORJ） in the field of space. A passive multi-channel space-borne FORJ has been designed. Firstly, the potential problems and challenges that the device may face when operating in space environments are analyzed. Then, targeted reliability design is carried out based on mature technical solutions. Finally, the designed space-borne FORJ is experimentally verified. The experimental results indicate that the proposed passive multi-channel space-borne FORJ meets the requirements of space applications.