In order to enrich the knowledge on the benthic macroinvertebrates in the middle reach of Yangtze River, a one-year investigation from March 2009 to March 2010 on secondary production and trophic basis of the dominant caddisfly in Shengli River (Shengli Town, Luotian County, Hubei Province), Bahe catchment, the middle reach of the Yangtze River Basin, was conducted. The result showed that the dominant caddisfly Hydropsyche sp. was trivoltinism. From the 1st to 4th rivers, the annual average biomasses of this species are 1.77, 7.80, 44.82 and 51.55 mg/m², respectively. Its annual production and P/B calculated with size (instar) -frequency method is 7.71 g/m2 and 13.21, respectively. Foregut content analysis showed that amorphous detritus was the dominant food of Hydropsyche sp., constituting 45.22%-62.92%, while the animal material usually gave the biggest contribution to secondary production, up to 52.86%-68.58%. In spring, amorphous detritus occupied the largest proportion and contributed most production, while in summer, autumn and winter animal material contributed the largest part of production. The annual ingestion currency of the species in different order rivers was 11.83 g/(m2 ·a) for 1st, 34.76 g/(m2 ·a) for 2nd, 237.52 g/(m²·a) for 3rd, and 273.17 g/(m²·a) for 4th, respectively. The study indicated that this caddisfly played an important role in the material cycling and energy flow of the Shengli River ecosystem.