Recently, biodiversity research has expanded from community species diversity to functional diversity. The use of species traits to characterize the functional composition of benthic invertebrate communities has become well established in ecological literature. This approach could potentially predict changes of both species and communities along environmental gradients in terms of traits that are sensitive to local environmental changes. With the aim of understanding the influence of environmental factors on the spatial distribution patterns of trait composition and functional diversity of aquatic insects, macroinvertebrates were surveyed at 12 sites along 4 rivers (i.e., Xiangxi, Jiuchong, Gaolan, and Gufu Rivers) in the Xiangxi River system during a period of low flow (from December 2005 to February 2006). Simultaneously, water samples were collected at each site and transported to the laboratory, where the concentrations of 6 parameters (TN, TP, NO₂-N, NO₃-N, NH₄-N, and PO₄-P) were determined. Other physical and chemical parameters were measured in the field. Based on published datasets and expert opinion, we compiled information on 10 biological and ecological traits of aquatic insects including voltinism, occurrence in drift, swimming ability, attachment, shape, size at maturity, rheophily, thermal preference, habit, and trophic habit. A total of 127 taxa were collected; Baetis sp., Epeorus sp., Nemoura sp. were the dominant taxa, with relative abundances of 38.6, 9.1, and 6.7% respectively; the dominant taxa compositions were significantly different among the 4 rivers (P <0.05). One-way ANOVA and independent samples T test were performed to compare the traits which showed that the proportion of Volt1 (univoltine), Drft2 (common occurrence in drift), Swim2 (weak swimming ability), Atch1 (none of attachment), Atch2 (some of attachment), Size3 (large size at maturity), Rheo1 (depositional rheophily only), Ther3 (warm eurythermal), Habi2 (climber), Habi3 (sprawl), Trop3 (herbivore), Trop5 (shredder) were significantly different among the 4 rivers (P <0.05). Modified functional attribute diversity and functional diversity based on a dendrogram were calculated to characterize functional diversity in the Xiangxi River system, and the results showed that the Jiuchong River had the highest modified functional attribute diversity (6.9), followed by the Xiangxi (5.4), Gaolan (3.2), and Gufu (2.8) Rivers; functional diversity based on a dendrogram and functional redundancy index also showed the same pattern. One-way ANOVA analysis showed that these 2 functional diversity indices all showed Jiuchong River > Xiangxi River > Gaolan, Gufu Rivers; and the functional redundancy index showed Jiuchong River ≥ Xiangxi River ≥ Gaolan River ≥ Gufu River. Finally, a stepwise regression analysis was conducted to exam the relationship between functional indices and physicochemical parameters. The results showed that modified functional attribute diversity was significantly impacted by total nitrogen, and water depth; whereas functional diversity based on a dendrogram was impacted by total nitrogen, water depth, and flow velocity; and functional redundancy was affected by nitrate-N, dissolved oxygen, and silicon dioxide.