The hydrodynamic environment of habitat has an important influence on the survival and reproduction of fish.Aiming at Wanglongqi Reach which is in the upper reaches of the Yangtze River，we use three-dimensional flow numerical simulation method to discuss the influence of waterway regulation project on the hydrodynamic indexes of the spawning habitat of Myxocyprinus asiaticus.The results reveal that the velocity distribution of each section of the river is “high in the middle and low on both sides” along the river width.After the regulation project，the optimum spawning velocity area of each section shifts to the right，and the offset increases with the increase of the flow，with the maximum offset of 60 m.The vorticity is distributed in layers along the water depth，with a general pattern of “large in bottom layer and small in surface layer”.After the regulation project，large vorticity values are concentrated in the vicinity of the project area and in the middle of the river section，and the vorticity distribution is changed significantly along the vertical line.With the increase of the flow rate，the vorticity variation are amplitude increased，and the maximum variation amplitude is 0.05 s-1.The distribution of kinetic energy gradient along water depth is similar to that of vorticity，and the characteristics of kinetic energy gradient distribution along river width are strongly correlated with water depth.The maximum kinetic energy gradient of each section is increased with the increase of flow rate.The complex hydrodynamic conditions formed after the regulation project are conducive to the survival and reproduction of fish.