The results of a year's research on the benthic community in the Acquarella area of Lake Bracciano are reported. Fifty-three taxa of benthic invertebrates were collected. The fauna is mainly represented by gastropods (in the littoral), chironomids and oligochaetes (especially in the sublittoral and profundal zones). There are numerous other taxa, particularly in the littoral. The diversity indices (Shannon's diversity and evenness) were also calculated. The results suggest that the area investigated still exhibits unpolluted environmental conditions.