The influence of small hydropower plants (SHPs) on the spatial distribution of macroinvertebrate assemblages was investigated in five cascade SHPs along the Xiangxi River in October 2005. Five sites were sampled at each SHP. A total of 4656 macroinvertebrates belonging to 69 genera were collected. The characteristics of macroinvertebrate community structures were analyzed by using richness, abundance, dominant species and functional feeding groups. The results suggested that the construction of the SHPs had no significant impact on water chemistry, but physical variables (such as current velocity and water depth) varied significantly among the five sites. All the characteristics of the macroinvertebrate community were more or less affected by the construction, especially the abundance, filter-collecters percentage and predators percentage were significantly affected by the stations. The results also suggested that the sites beneath the dam had most different community structures, which indicates that diverting the water current completely is harmful to the protection of macroinvertebrate diversity of the river.