Interest in the study of wet deposition N continues to grow for its impact on terrestrial ecosystems. Assessing the contribution of wet deposition N to intensive croplands is significant for recommending N fertilizers and minimizing environmental hazards. NH 4 + –N, NO 3 − –N, and total N concentrations in wet deposition, seasonal deposition N fluxes, and N loads in event-based runoff were determined for four consecutive wheat seasons in the Tai Lake Region. Wet deposition N during wheat seasons ranges from 11 to 15kgha −1 (average, 13kgha −1 ), 61% of which is in the form of NH 4 + –N. NH 4 + –N concentrations range from 0.3 to 8.5mgNL −1 (average, 1.7mgNL −1 ), showing greater temporal variations than do those of NO 3 – –N, which range from 0.2 to 4mgNL −1 (average, 0.8mgNL −1 ). NH 4 + –N concentration in event-based runoff from wheat fields is much lower than that in rainfall, whereas that of NO 3 – –N is equal to or higher than that in rainfall. N loss through runoff reaches 1.8kgNha −1 , accounting for 14% of wet deposition N. Results indicate that NH 4 + –N in wet deposition is prone to immobilization by the soil–crop system, whereas NO 3 – –N is relatively easily lost to runoff. The contribution of 11kgha −1 wet deposition N should be adjusted in fertilizer N recommendations for winter wheat cultivation in this region.