The freshwater crabs of the genus Tiwaripotamon Bott, 1970 (Potamidae) are revised and the identities of two poorly known species, T. simulum (Alcock, 1909) and T. araneum (Rathbun, 1905), are clarified after a re-examination of the types. Tiwaripotamon, sensu stricto, is restricted to five species, T. annamense (Balss, 1914); T. araneum (Rathbun, 1905); T. pingguoense Dai and Naiyanetr, 1994; T. xiurenense Dai and Naiyanetr, 1994; and a new species, T. edostilus, from Vietnam. Tiwaripotamon simulum is transferred to the genus Kanpotamon Ng and Naiyanetr, 1993. Keys to the species of Tiwaripotamon and Kanpotamon are also provided.