<jats:title>Abstract</jats:title><jats:p>Five new C<jats:sub>19</jats:sub>‐diterpenoid alkaloids, named hemsleyaconitines A–E (<jats:bold>1</jats:bold>–<jats:bold>5</jats:bold>, resp.), were isolated from <jats:italic>Aconitum hemsleyanum</jats:italic> <jats:sc>Pritz.</jats:sc> By UV, IR, MS, 1D‐ and 2D‐NMR analyses, their structures were elucidated as 18‐dehydroxygeniculatine D (<jats:bold>1</jats:bold>), 6‐hydroxy‐14‐<jats:italic>O</jats:italic>‐veratroylneoline (<jats:bold>2</jats:bold>), 14‐<jats:italic>O</jats:italic>‐acetyl‐8‐ethoxysachaconitine (<jats:bold>3</jats:bold>), 18‐veratroylkaracoline (<jats:bold>4</jats:bold>) and 8‐<jats:italic>O</jats:italic>‐ethylaustroconitine B (<jats:bold>5</jats:bold>).