The benthic macroinvertebrate were selected at the wadeable streams using the survey design of the West Environmental Monitoring and Assessment Program (WEMAP). A total of 1,700 samples were selected from 2000 to 2004. Totally 617 species were identified and the dominant species were Polypedilum sp., Baetis sp., and Tanytarsus sp. The species abundance distribution patterns of benthic macroinvertebrate communities were analyzed at the intermediate and the large scale. The ranked abundance showed shallow slope basically exhibiting S-shape form, bending up at the left part and bending down at the right part. It indicated the rare species and the abundant species were rare, and most species had intermediate dominance. Correspondingly, the species abundance distributions were mainly fitted to the log normal distribution in benthic macroinvertebrate communities