In space laser communication system, acquisition, tracking and pointing (ATP) technology is quite important. The pointing precision of the ATP system is a decisive factor in the success of the whole communication system. The artical mostly analyzes the compound axis tracking in space laser communication system. Firstly, the conception of the optical inter-satellite communications and the excellences of realizing the inter-satellite communications by laser are introduced. Then the traits of compound axis tracking are analyzed, the field of view matching of compound axis tracking and its capability analysis are given. Finally, through the simulation and comparison the conclusion that choosing appropriate bandwidth and bandwidth ratio can restrain system error is obtained.