Based on the assumption of single-scattering, atmospheric propagation model of non-line-of-sight optical scattering communication system is studied. The model is used to analyze the correlations between received scattered energy and parameters of system, including source divergence angle, receiver field of view, and apex angles of transmitter and receiver in an optical scattering communication system. Contribution of atmospheric molecular scattering and aerosol scattering of received scattered energy is discussed. The results show that received scattered energy is attributed to molecular scattering at larger transmitter and receiver apex angles, but with the decrease of apex angles, aerosol scattering will be dominant in received scattered energy. Enhancing of the receiver field of view can effectively improve the signal noise ratio for communication systems operating in the solar-blind ultraviolet (UV) spectral region. In addition, the evolution tendency of received scattered energy versus the source divergence angle is inverse for two typical transmitter and receiver apex angles. This result suggests that divergence angle of source should be designed according to specified situation.