A new species of Deinostigma ( Gesneriaceae ) from Yunnan, China, Deinostigma fasciculatum W.H.Chen & Y.M.Shui, sp. nov., has been discovered and described. In the genus, the new species is similar to D. cicatricosum (W.T. Wang) D.J. Middleton & Mich. Möller and D. cyrtocarpum (D. Fang & L. Zeng) Mich. Möller & H.J. Atkins in dark purple flowers and falcate fruit, but differs from them mainly in the inflorescences with fasciculate flowers, calyx lobes (reflexed, narrowly lanceolate and 1.2–1.3 cm long), corolla tubes (sharply contracted below middle and white outside and below throat). The above three species grow nearby non-limestone wet cliffs and geographically isolated with different distributions (the new species in Southeast Yunnan, D. cicatricosum in Eastern Guangxi and D. cyrtocarpum in Southern Guangxi and Guangdong, China).