Abstract: In this paper, the statistical characteristics of acoustic transmission loss in shallow water caused by fluctuant surface scattering in different seasons are studied based on the marine environmental data, small slope approximation of the fluctuant surface and normal mode method. A formula fitting the relationship between wind speeds and surface scattering transmission loss is proposed, accompanied with a fast method for sound field prediction. These works can contribute to the rapid evaluation of the performance of long-working underwater acoustic equipment. It is shown that for the underwater acoustic equipment, the influence of fluctuant surface scattering on sound propagation cannot be ignored, when the transmission distance exceeds 10 km. In addition, such influence in winter is greater than that in summer. Furthermore, in the negative thermocline environment in summer, the influence of fluctuant surface scattering on the sound filed with source below the thermocline and the receiver above the thermocline is greater than that on the sound filed with source and receiver both below the thermocline.