The survey was made in Xijiang River from 2005 to 2008. Ninety species belonging to 13 orders29 families and 75 genura were collected from 6 sampling spots. Eight species including were newly recorded in Xijiang River. There is 17 species whose relative density >1relative density of 28 species < 0.1. The top 5 species in relalitive density were Fish communities were dominated by sedentary species and omnivore species. Compared with the historic datathe proportion of omnivore and sedentary species increased. For carnivoremigratory and half-migratory species declined in number. The fish community of Xijiang River can be distinguished as three clustermiddle reach cluster and downriver cluster. The results indicated that fish species diversity in Xijiang River were significantly different among different sections. Fish species in similar habitats had higher similarity. The diversity of species in the upper stream is higher than that in the downstream. It also showed that these fish species living at downstream of the river with inferior mouthdecreased greatly in number especially for the carnivore through the individual ecology index. While these with terminal mouthadept to slow current become the dominated species. It is recognized that sea-route renovationwater pollution and excessive catching is the key factors to impact fish assemble in Xijiang River.