Atmospheric inorganic nitrogen and sulfur deposition samples were collected from May 2017 to April 2018 at the Zhongliang mountain trough valley in the suburbs of Chongqing. The ratio of ionic concentrations, isotope value, and air mass backward trajectories model were used to trace the sources of atmospheric nitrogen and sulfur. Our analyses showed that:(1) During the monitoring period, total atmospheric DIN deposition flux was 19.99 kg/hm², among it the dry and wet deposition flux accounted for 11% and 89%, respectively. The total atmospheric S deposition flux was 32.62 kg/hm², among it the dry and wet deposition accounted for 13% and 87%, respectively. The atmospheric N and S dry and wet deposition flux exhibited clear seasonal changes, which were positively correlated with precipitation (n=12, P < 0.01).(2) The ratio of NH₄⁺-N/NO₃^--N was from 0.45 to 2.2, being greater than 1 in the rainy season (May to October) and less than 1 in the dry season (November to April of the following year), indicating that the sources of nitrogen were mainly from agricultural activities in the rainy season, and from industrial and traffic sources in the dry season. The ratio of NO₃^-/SO₄^2- was from 0.1 to 1.25, with a mean value of 0.63, indicating that the source of sulfur was mainly from coal burning. (3) The δ¹⁵N-NO₃^- and δ¹⁸O-NO₃^- values of rainwater were characterized by negative values in summer and positive values in winter, ranging from -3.8 to 3.9‰ (mean 0.4‰±2.6‰) and 58.7 to 98.7‰ (mean 76.1‰±14.3‰), respectively. The δ³⁴S-SO₄^2- and δ¹⁸O-SO₄^2- values of rainwater ranged from 1.3 to 3.2‰ (mean 2.3‰±1‰) and 5.3‰ to 8.5‰ (mean 7.1‰±1.6‰), respectively. Dissolved NO₃^- and SO₄^2- in rainwater were derived mainly from local fossil fuel combustion, but were also affected by transmission of pollutants from surrounding areas. (4) Air mass backward trajectories indicated that East Asian monsoon was the main factor affecting the dry and wet deposition of nitrogen and sulfur in the study area, and the large geomorphic pattern running northeast to southwest of the eastern Sichuan parallel gorge has aggravated the influence of the East Asian monsoon.