Chunia bucklandioides, a threatened species of the monotypic Chunia (Exbucklandioideae, Hamamelidaceae) that was known only from Hainan Island, China, is reported here for the flora of Vietnam. Chunia bucklandioides is most similar to Exbucklandia populnea, but differs from it mainly by floral characters such as inflorescences (spicate 12–16-flowered vs. capitate 8–12-flowered), filament length (3–4 mm, somewhat shorter or as long as anther vs. ca. 5 mm, much longer than anther), anthers (4-locular vs. 2-locu-lar), and anther color (red vs. yellowish). Chunia bucklandioides also resembles Mytilaria laoensis, but is easily distinguished from it by morphological characters of stipules (in pairs, broadly ovate, subrounded vs. solitary, conical) and sepals and petals (absent vs. present). In addition an extended taxonomic description, we provide habitat details, illustrations and assessment of the conservation status of C. bucklandioides.