The population size, distribution, threats and conservation status of 2 bat species included as 'endangered' in the IUCN Red List were assessed in Thailand and Myanmar. Craseonyc- teris thonglongyai Hill, 1974 and Hipposideros turpis Bangs, 1901 are both rare and poorly known cave-dwelling species, which have restricted distributions and small population sizes. Surveys of the 2 species were conducted in a large number of locations including previously reported sites and potential new locations. Colony size was counted at currently known localities, and population size was estimated. The known distribution and population are larger than in previous estimates, but both species still remain threatened by roost disturbance and the destruction of foraging habitat. Clarifi- cation of the taxonomic status of allopatric populations within each species is urgently required.