In order to optimize the regulation scheme of Shegong River located in the comprehensive development area of Guangzhou Baiyun international airport, a flood hazard analysis for the Tieshan River watershed was made by coupling one-dimensional MIKE11 and two-dimensional MIKE21 hydrodynamic model with the MIKEFLOOD to simulate the basin inundation situations in the case of the floods in different recurrence periods. The results show that the area of flooding inundation range in Shegong River basin is 4.03km², the maximum inundation depth is 0.93m, and the inundated area is mainly located in the middle and lower reaches with strong development intensity, while there is a certain flood discharge capacity in the lower reaches of Tieshan River when encountering the flood with a return period of 20 years. A regulation scheme that two new branches should be built to pit the flood in the middle and lower reaches of Shegong River into the lower reaches of Tieshan River was drawn up.