The effects of nitrogen management on rice yield and lodging resistance characteristics of rice in the rice-crayfish coculture were studied, by two interactive experiments of different rice cropping modes (rice monocropping, rice-crayfish coculture) and nitrogen fertilizer management (no nitrogen application, conventional nitrogen application, and nitrogen-reduction application). The results showed that, the rice yields of the conventional nitrogen application treatment and nitrogen reduction treatment under rice-crayfish coculture were 7 539 kg/hm² and 7 328 kg/hm², respectively, which were 29.4%-32.3% lower than those of the rice monocropping. It was mainly caused by the continuous rainfall after rice transplanting in the experiment year, and also related to the decrease in the number of effective panicles, grains per panicle and 1000-grain weight of rice under deep-water flooding. Compared with rice monoculture, the plant height, panicle length, the gravity center height, the bending moment and lodging index of the rice-crayfish coculture increased by 12.9%, 17.9%, 8.0%, 20.9% and 33.5% on average, the thickness of culm wall, breaking resistance, and breaking moment of the second internode decreased by 38.7%, 16.8% and 16.6% on average. In the rice-crayfish coculture mode, compared with the conventional nitrogen application treatment, the breaking resistance of the second internode of the rice stem in the nitrogen reduction treatment increased by 13.5%, and the lodging index decreased by 1.8%, rice yield reduced only 2.9%. Correlation analysis showed that the stem wall thickness was extremely significantly negatively correlated with lodging index (p<0.01), and the plant height and bending moment were significantly negatively correlated with breaking resistance (p<0.05). The rice-crayfish coculture can ensure stable rice yield, reducing application amount of nitrogen fertilizer can improve the lodging resistance under this mode and reduce the lodging risk.