ABSTRACT: Three samples from the Cibolo Formation (Leonardian, lower Permian) of the Chinati Mountains in southwestern Texas are analyzed for fusulinid biostratigraphy, and fusulinid data from previous studies in the Chinati Mountains are summarized. Sample R0900 from the allochthonous Cibolo reef block contained only Chusenella cibolensis and is probably early Leonardian in age. Sample 4E1 from 50-100 ft (15.24-30.48 m) above the base of the Cibolo Formation contained Schwagerina crassitectoria, S. guembeli, and ?Pseudoreichelina nevadaensis, which are typical of early Leonardian strata in the Permian Basin region (Zone Lf1). Sample 2-40 from 420 ft (128 m) above the base of the Cibolo Formation contained Parafusulina durhami, P. fountaini, P. guatemalaensis, and P. bakeri, which are late Leonardian in age (Zone Lf3). No samples containing middle Leonardian fusulinids (Zone Lf2) were found.