Abstract: A field experiment was conducted to study the after-effects of nitrogen applied at different rates (0, 60, 120, 180 kg/ha) to wheat on the yields and agronomic traits of a subsequent soybean monoculture (wheat-soybean cropping system) and soybean intercrop (wheat/maize/soybean intercropping system) in the 2013-2014 growing season. The results showed that soybean in both monoculture and intercropping systems made full use of the after-effect of nitrogen applied to wheat. The biomass and grain yield of soybean first increased and then decreased as the rate of nitrogen application to wheat increased. The highest biomass and grain yield of monocropped soybean and the highest yield of intercropped soybean (4133 kg/ha) were in the N₁₂₀ treatment. The biomass of monocropped soybean was 62.3% higher than that of intercropped soybean at the branching stage, but the biomass of intercropped soybean was 57.9% higher than that of monocropped soybean at the harvest stage. Compared with monocropped soybean, intercropped soybean showed 63.9% higher grain number per plant and 55.9% higher yield. The 100-grain weight did not differ significantly between intercropped and monocropped soybean. The grain yield from the main stem and branches accounted for 54.2% and 45.8%, respectively, of the total yield of monocropped soybean. However, grain yield from the branches accounted for 68.9% of the total grain yield of intercropped soybean. Although the lodging rate was 5.2% higher for intercropped soybean than for monocropped soybean, the empty sticks rate was 78.0% lower and the blighted pod rate was 25.4% lower for intercropped than for monocropped soybean. The percentage of branch grain yield increased with increasing nitrogen application to wheat. The main stem length of intercropped soybean (average, 39.5 cm) was 6.2 cm longer than that of monocropped soybean (average, 33.3 cm) at the branching stage while that of monocropped soybean (average, 84.8 cm) was 10.4 cm longer than that of intercropped soybean (average, 74.4 cm) at the harvest stage. The length of the first stem was greater in intercropped soybean (8.3, 6.6 cm) than in monocropped soybean (5.6, 4.6 cm) at both branching and harvest stages. The average number of branches was higher in monocropped soybean (1.9) than in intercropped soybean (0.7) at the branching stage, while that of intercropped soybean (6.1) was higher than that of monocropped soybean (3.5) at the harvest stage. The number of branches significantly increased with increasing nitrogen application to the former wheat crop. These results indicated that the soybean was able to utilize the residual N from nitrogen applied to wheat in both the wheat-soybean and wheat/maize/soybean systems. Although growth of intercropped soybean can be affected by maize, intercropped soybean can recover rapidly and resume rapid growth after the maize is harvested. The number of branches, pods, and filled pods as well as the grain yield can be increased through adjusting the amount of nitrogen applied to former crops.