Based on material recently collected in Piauí state, northeastern Brazil, we present new records for seven species of Gerromorpha (Insecta, Hemiptera, Heteroptera). Rheumatobates crassifemur schroederi Hungerford, 1954 (Gerridae); Mesovelia mulsanti White, 1879 (Mesoveliidae); and Paravelia polhemusi Rodrigues, Moreira, Nieser, Chen & Melo, 2014 (Veliidae) are reported from the state for the first time.