In order to provide design basis for blue-green laser communication system, a standard atmospheric attenuation model in mid-latitude region was used to analyze the effects of weather phenomena, turbulence intensity, divergence angle and receiving aperture on link margin, signal-to-noise ratio and bit error rate, combined with atmospheric attenuation, geometric attenuation and atmospheric turbulence. The analysis results show that the link margin is related to divergence angle and receiving aperture, while the signal-to-noise ratio and bit error rate are only related to receiving aperture. At the same time, on sunny days, the smaller the divergence angle and the larger the receiving aperture, the larger the link margin is; the weaker the turbulence intensity, the larger the receiving aperture, the larger the SNR is and the smaller the bit error rate is.