The concept of the bidirectional laser link tracking stability in inter-satellite optical communication is proposed for the problem of short effective time of the signal transmission in the current and the influence of various factors on the tracking stability is analyzed. Considering receiving signal-to-noise ratio(SNR), relative motion velocity, link performance requirements and other factors, expectation formulas of tracking stability time are established. A relatively complete simulation model of bidirectional laser link tracking in inter- satellite communication with Simulink is established, which can prove the correctness of the theory formula. To maintaing inter-satellite optical communication link stability for a long time, a method utilizing different control parameters at different velocities between the satellites is proposed, and the control strategy in inter- satellite optical communication terminal is optimized. The results of this paper are significant for the aerospace engineering of satellite optical communications.