The study on the distribution characteristics of fish spawning habitat suitability is of great significance for river ecological protection.Taking the Zhongpanzi bend which is located in the upper reaches of the Yangtze River as an example and based on the 2-D numerical simulation data of planar water flow,we studied the distribution regularity of spawning habitat suitability of four major domestic fishes in the mountainous meandering river.The results show that the most suitable area for fish spawning will change with flow:when the flow is small,the most suitable area is in the deep groove;and with the increase of the flow,the area is mostly located in the side beach. Suitable area of micro-habitat SA increases first and then decreases with flow Q,and the peak value of SA appears near the annual average flow. The velocity suitability SV is relatively large on both sides of the river,while the deep suitability SD and the habitat suitability index SH are relatively large on the thalweg of the river.SD and SH on concave bank and convex bank are correlated,and SH increases linearly with SD.Under the multi-year average discharge,the distribution of SD along the river width is characterized by small at both ends and large in the middle.The distribution of SV and SH along the river width coincides with each other,and the numerical difference is mainly reflected in the vicinity of the two banks.The area of SH＞ 0.8 mainly concentrates on both banks of the river and concave shore beaches,which is more suitable for fish spawning.The research results can provide scientific reference for the protection of fish resources and the construction of ecological waterway projects in mountainous rivers.