Wet and dry deposition samples were collected from September 2020 to August 2021 at a suburban site in Mianyang, Southwest China. Major water-soluble inorganic ions (WSIIs) in daily rainfall samples and integrated dry deposition samples were determined using ion chromatography. In rainfall, the annual volume-weighted mean (VWM) concentrations of SO₄^2-, NO₃^-, NH₄⁺, and Ca²⁺ were 30.1, 28.7, 64.9, and 31.8 μeq L^-1, respectively. The annual values of acid-neutralizing capacity and fractional acidity were 37.8 μeq L^-1 a nd 0.0035, r espectively, indicating that SO₄^2- and NO₃^- in the rainfall were fully neutralized by NH₄⁺ and Ca²⁺, which was supported by the annual rainfall pH of 6.7. The annual wet and dry deposition fluxes were 0.27 and 0.09 keq ha^-1 yr^-1 for SO₄^2- and 0.26 and 0.11 keq ha^-1 yr^-1 for NO₃^-, respectively, resulting in a total acid deposition flux of 0.73 keq ha^-1 yr^-1, which approximated the maximum critical load of acidity in Sichuan province. The annual wet and dry deposition fluxes were 8.3 and 2.9 kg N ha^-1 yr^-1 for NH₄⁺-N and 3.7 and 1.5 kg N ha^-1 yr^-1 for NO₃^--N, respectively, leading to a total nitrogen deposition of 16.4 kg N ha^-1 yr^-1. Moreover, the annual equivalent ratio of [SO₄^2-]/[NO₃^-] in rainfall was 1.1, suggesting that the acid deposition in Mianyang was a mixed type caused by sulfuric and nitric acids. The annual mass ratio of NH₄⁺-N/NO₃^--N was 2.3, reflecting the important role of agricultural activities in nitrogen deposition in Mianyang.