Global nitrogen deposition has a profound impact on terrestrial ecosystems. Studying the effects of long-term nitrogen (N) deposition on the soil physical and chemical characteristics of the grassland ecosystem help to understand the permanent mechanism of ecosystem response to nitrogen deposition. In this study, six gradients of urea application (0, 2, 4, 8, 16 and 32 g N m^-2 a^-1, treatments demonstrated as N0-N32) were applied to simulate N deposition for 14 consecutive years, and the soil samples were collected with three soil depths (0-10, 10-20, 20-40 cm from soil surface), to study the response of soil carbon (C) and nitrogen (N) components and physical structure to N addition and their correlations in temperate grassland ecosystem. The results showed that: (1) N addition significantly reduced soil pH and microbial biomass carbon (MBC) in the 0-10 cm soil layer, and N32 decreased by 27.63% and 58.40% (P<0.05), respectively, compared with N0. The content of total organic carbon and total nitrogen in all soil layers showed no significant response to N addition treatment, but the content in 0-10 cm soil layer was significantly higher than that in 20-40 cm soil layer. (2) N addition at each soil depth significantly increased inorganic nitrogen (ION) content (P<0.05); The ammonium nitrogen content in the 0-10 cm soil layer increased by 88.72% compared to N0, and the nitrate nitrogen content in the 20-40 cm soil layer increased by 19.55 times compared to N0; Soil depth and N addition had significant interaction effect on ION. (3) There was no significant difference in the fractal dimension of soil particle sizes or soil aggregates at each soil depth, and correlation analysis demonstrated that soil carbon and nitrogen nutrient contents were significantly associated with the soil structure. In conclusion, the increasing trend of C and N components in soil with optimal N addition concentration indicates that N addition may favor soil physical and chemical properties to some extent, thus the effect of N addition on soil physical structure needs further in-depth study.