Three species of water beetles, 2 dytiscids and 1 hydrophilid, from Mt. Roraima and Ptari‐tepui in the state of Bolivar, Venezuela, are discussed. One dytiscid,Tepuídessus brewerin. gen., n. sp., and the hydrophilidTropisternus jolyin. sp., are described and distinguishing characters are illustrated. The new taxa are compared to related ones and their habitats are discussed. Also, a collection ofRhantus elegansWaterhouse is reported for the first time since the species was described in 1895. The male genitalia ofR. elegansis illustrated for the first time and its habitat also is described.