<jats:title>Abstract</jats:title><jats:p>Two new triterpenoid alkaloids, buxmicrophyllines J and K (<jats:bold>1</jats:bold> and <jats:bold>2</jats:bold>, resp.), together with four analogues, <jats:bold>3</jats:bold>–<jats:bold>6</jats:bold>, were isolated from the leaves and stems of <jats:italic>Buxus microphylla.</jats:italic> The structures of the new compounds were elucidated by NMR and MS spectroscopic analyses. The partial assignments of the NMR spectra of <jats:bold>3</jats:bold> were also revised. Compounds <jats:bold>1</jats:bold> and <jats:bold>3</jats:bold>–<jats:bold>6</jats:bold> were evaluated for their growth inhibitory activity against human cell lines HL‐60, SMMC‐7721, A‐549, SK‐BR‐3, and PANC‐1. Compound <jats:bold>6</jats:bold> showed significant cytotoxicity against HL‐60, SK‐BR‐3, and PANC‐1 cell lines, with <jats:italic>IC</jats:italic><jats:sub>50</jats:sub> values of 6.46, 19.61, and 28.57 μ<jats:sc>M</jats:sc>, respectively.