Abstract: The structure of optical path coupling transmission system between platforms and the realization method for optical axis stability control are introduced in this paper. The coupling correction system and detection control system are designed, and the dynamic range and modal simulation of the correction system are carried out, followed by the developent of the beam coupling transmission and control system after design optimization. After testing the performance parameters of the fast mirror, we carried out the platform coupling transmission and control experiments. When the shaking table was loaded with 0 dB vibration spectrum and the control system was open-loop, the X-axis jitter was 10.9″@RMS and the Y-axis jitter was 102.3″@RMS. When closed-loop, the X-axis jitter was 0.75″@RMS and the Y-axis jitter was 1.11″@RMS. Spectrum analysis shows that when the fast mirror optical axis coupling system is closed-loop, it has a good suppression effect on the optical axis jitter within 28 Hz. The suppression ratio is from −40 to −30 dB in the frequency range of 2～6 Hz with large open-loop residual error. The experimental results prove that the optical axis coupling control system has a good effect of suppressing and stabilizing the beam jitter in the process of beam transmission between platforms.