Schizostachyum langbianense is a new woody bamboo from a high mountain, Lang Bian, in southern Vietnam, which is being described and illustrated. It is similar to S. ninhthuanense in having short ultimate inflorescence branchlets on which clusters of a few pseudospikelets are borne. However, it differs in its culm leaves with a horizontal or only slightly concave apical portion, culm leaf blades that are narrowly lanceolate, and a palea that is not apically bifid and dorsally sulcate with 2 keels. Both species occur in the same mountain region, but separated by distinct elevations.