Surveys for larval mosquitoes were conducted in West Virginia from 1992 through 1997. A total of 26 species were identified with the frequency of occurrence for each species determined by elevation category, month of collection and association with one or more of 15 defined larval habitat types (7 sunlit and 8 shaded). Larvae of Anopheles punctipennis, Culex restuans, Cx. territans and Ochlerotatus triseriatus (in rank order) were the most commonly encountered species. Anopheles punctipennis and Cx. territans were more likely to be found at low (<457 m) elevations, whereas Cx. restuans and Oc. triseriatus were more frequently encountered at elevations of 457 to 914 m. Ochlerotatus canadensis first appeared in February, but after May this species was encountered in <1.0% of monthly collections. No other species (with the exception of Oc. triseriatus which first appeared in March) appeared before April. Anopheles punctipennis and Cx. territans larvae were found in the most habitat types (14 of 15) and both, along with Cx. restuans, were significantly more likely to be collected in sunlit conditions. Conversely, the likelihood of encountering Oc. triseriatus was significantly greater in shaded habitats. Precise frequencies of occurrence are given for all 26 mosquito species by elevation category, month of collection and each defined larval habitat type.