For the applications of the infrared laser communication system in the quasi-horizontal propagation path near the ground,diurnal variations of the atmospheric visibility and the refractive index structure constant were continuously measured in Jinan，Shangdong Province,for seven days.The key atmospheric parameters impacting on the performance of laser communication system were obtained.The influences of the extinction and turbulence channels on BER (Bit Error Rate) and ES (Error Second) were also analyzed for one kilometer communication chains.Furthermore,the feasibility and reliability of communication system were discussed under the complex atmospheric conditions.The methods for attenuating the effects on the performance of laser communication system were summarized and discussed.