Didymocarpus tonghaiensis J. M. Li & F. S. Wang sp. nov. from Yunnan, China, is illustrated and described. It is morphologically similar to D. stenanthos C. B. Clarke, but differs by having a densely glandular peduncle, 5-lobed calyx with lobes that are free to the base, larger corolla, anther with white woolly hairs and a densely glandular-hairy capsule.