Marine aerosols are important components of atmospheric aerosols. In order to study their impact on quantum communication, for a given transmission distance we have therefore analyzed the dependence of the link attenuation on the concentration, size-spectrum distribution, and extinction coefficients of the marine aerosol particles. In particular, we have studied and simulated the quantitative relationships of particle concentrations and transmission distance on the link attenuation, channel capacity, channel fidelity, and channel error rate. The simulation results show that when the transmission distance is 8 km and the ocean aerosol particle concentration is 300/m ³ and 500/m ³, the corresponding link attenuation, channel capacity, and channel bit error rate are 0.407 dB/km and 0.679 dB/km, 0.423 bit/s and 0.349 bit/s, 0.027 and 0.092, respectively. When the concentration of ocean aerosol particles is 500/m ³ and the transmission distance is 5 km and 7 km, the corresponding channel fidelity is 0.911 and 0.849, respectively. Ocean aerosols thus have varying degrees of influence on the performance of free-space quantum communication. In actual quantum communication, various performance parameters must therefore be adjusted according to the concentration of the ocean aerosol particles in order to ensure normal communication.