In view of the existing calculation of the attenuation of blue-green laser underwater, the same kind of sea water is estimated by fixed attenuation coefficient, but the actual attenuation coefficient of different sea areas is different, which leads to the problem that some theoretically feasible areas cannot communicate normally. A new method is proposed to calculate the transmission of blue-green laser underwater based on the transparency remote sensing observation data. According to the moderate-resolution imaging spectroradiometer(MODIS) remote sensing data is used to retrieve the attenuation coefficient of blue-green laser in some areas of the Yellow Sea, this paper analyzes the temporal and spatial distribution characteristics of the attenuation coefficient of the Yellow Sea, estimates the transmissivity of 50 m underwater, and evaluates the feasibility of blue-green laser communication. It is concluded that the higher the transparency is, the smaller the attenuation coefficient is, and the higher the transmittance is when the transmission distance is fixed; When the transparency is greater than 5.295 m, the attenuation of the laser at 50 m underwater is less than 40 dB, and the blue-green laser communication can be carried out.