Abstract: The ten-year ban on fishing in the Yangtze River is a major ecological strategy in China.To grasp the dynamics of fish resources is an important basis for scientific ban on fishing.Based on systematic survey data from 12 sections of the Hanjiang River in Shaanxi Province from 2022 to 2023, and combined with a historical data comparison, this study analyzed fish community structure and its spatiotemporal evolution characteristics, using the Shannon-Wiener diversity index, G-F index, relative importance index (IRI), and fish individual ecology matrix.A total of 93 fish species (belonging to 60 genera, 15 families, and 5 orders) were collected during the survey, with 55 Cyprinidae species and 13 Bagridae species accounting for 73.1% of the total.Three national protected species including Hucho bleekeri were recorded.Hemiculter leucisculus (IRI=1237) and Xenocypris davidi (IRI=1158) were the absolutely dominant species, accounting for 21.9% of the total catch.Compared to 1985, the overall similarity of fish communities was 0.56 (moderate similarity), indicating a significant species loss.Fish biodiversity in the main stream (H’=2.00) was significantly higher than that in the tributaries (H’=1.52).The G-F index (0.521) increased by 3.8%, compared to historical values, which reflected an increased inter-family diversity and a reduced intra-family diversity.The results showed that fish communities in the study area exhibited the trends of slow-flow adaptation (81.0% proportion), omnivorous feeding (81.0%), and miniaturization (<50 g individuals accounting for 65.7%).Although fish diversity had recovered to some extent after the implementation of the fishing ban, ecological functions had not yet fully recovered.It was recommended to restore habitat connectivity, regulate ecological water flow, and implement rescue protection for the endangered species to provide scientific support for ecological conservation in the Yangtze River Basin.