Four new triterpenoid alkaloid derivatives, buxrugulines A–D (1–4), together with four known ones (5–8), were isolated from the leaves and stems of Buxus rugulosa. The structures of compounds 1–4 were elucidated by NMR and MS spectroscopic analysis. All compounds were assayed for their cytotoxicities against HL-60, SMMC-7721, A549, MCF-7, and SW480 cells lines. [Figure not available: see fulltext.]. © 2011, The Author(s).