Aiming at the influence of urbanization on the spatial distribution of extreme precipitation, the urban canopy model combined with WRF(weather research and forecasting)mesoscale weather forecast model was used to simulate the “7·20” torrential rain in Henan Province in 2021. Combined with the measured precipitation data of national ground observation stations, the simulation accuracy of the model was verified. The results show that the coupling model considering the influence of urban canopy can better simulate the intensity and falling area of regional extreme precipitation, which is closer to the spatial distribution of measured precipitation. The average precipitation obtained by the coupling simulation is 12. 1 mm higher than that without considering the influence of urban canopy. Artificial water consumption changes the regional water heat coupling balance and promotes the formation of convective precipitation in urban areas.