Nitrogen concentration of epilithic mosses from the urban area to rural area at Guiyang was investigated systematically, and the level of atmospheric N deposition at each sampling site was calculated according to the quantitative relationship (y=0.052x+0.7325) between moss N concentration (y,%) and atmospheric N deposition (x, kg hm-2 a-1). The level of atmospheric N deposition ranged between 0.91-44.69 kg hm-2 a-1. The highest value (average (2921±6.17) kg hm-2 a-1) occurred at urban area (0-5km), which was mainly derived from higher NH3 release from city wastewater. The lowest level ((11.95±3.95) kg hm-2 a-1, 15-30km) at the combining area between the urban and rural area was mainly related to the reduced urban N pollutants, broad distribution of forest belt around the urban and lower agricultural intensity. Slightly higher N deposition ((14.31±5.11) kg hm-2 a-1) re-emerged over 20km from the urban center, showing the increase of agricultural NH3 release in rural area caused by fertilizer application. Consequently, N concentration of epilithic mosses was an economic and reliable tool in monitoring atmospheric N deposition, which could exactly quantify the level of atmospheric N deposition and,provide basic information for further studying the ecological and environmental effects of atmospheric N deposition.