<jats:title>Abstract</jats:title><jats:p>Four new myrsinol diterpenes, proliferins A–D (<jats:bold>1</jats:bold>–<jats:bold>4</jats:bold>, resp.) were isolated from the EtOH extracts of the roots of <jats:italic>Euphorbia prolifera</jats:italic>, along with four known compounds, euphorprolitherin B (<jats:bold>5</jats:bold>), euphorprolitherin D (<jats:bold>6</jats:bold>), SPr5 (<jats:bold>7</jats:bold>), and 14‐desoxo‐3‐<jats:italic>O</jats:italic>‐propionyl‐5,15‐di‐<jats:italic>O</jats:italic>‐acetyl‐7‐<jats:italic>O</jats:italic>‐nicotinoylmyrsinol‐14<jats:italic>β</jats:italic>‐acetate (<jats:bold>8</jats:bold>). Their structures were established on the basis of spectroscopic methods, including HR‐ESI‐MS, and 1D‐ and 2D‐NMR techniques. The cytotoxicity of compounds <jats:bold>1, 3</jats:bold>, and <jats:bold>4</jats:bold> against cancer cells was evaluated, with compound <jats:bold>1</jats:bold> being active against A2780 cancer cells.