During an amphibian biodiversity survey conducted in Tianlin County, Guangxi Zhuang Autonomous Region, China, a new species belonging to the genus Boulenophrys was identified and described as Boulenophrys tianlinensis sp. nov. This new species shares the closest genetic affinity with B. anlongensis (Li, Lu, Liu & Wang, 2020). Integrative taxonomic analyses, combining morphological characteristics and molecular phylogenetic data, confirm its status as a distinct species. The new species is distinguished from its congeners by a combination of the following characteristics: (1) medium body size, with snout-vent length (SVL) 34.3–39.0 mm in seven adult males and 47.1 mm in a single adult female specimen; (2) upper eyelid margin bearing one small horn-shaped tubercle on each side; (3) vomerine ridges present and vomerine teeth absent; (4) tongue not notched posterior; (5) tympanum rounded and clearly discernible; (6) toes with rudimentary webbing and lacking lateral fringes; (7) heels overlapping when thighs are held perpendicular to the body axis; (8) tibiotarsal articulation reaching the middle of the eye when the leg is stretched forwards; (9) males possessing a single subgular vocal sac; and (10) in breeding males, the nuptial pads have dark brown nuptial spines on the bases of the first and second fingers.