Four compounds were isolated from a petroleum ether extract of the pericarp of Lansium domesticum collected in Quang Nam Province. Their structures were determined using NMR (1H NMR, 13C NMR, HSQC, HMBC, and COSY) techniques. The compounds were two sesquiterpenoids, 6α,9β-dihydroxyeudesma-4(15)- ene and aphanamol II, along with two onocerane triterpenoids, 3β-hydroxyonocera-8(26),14-diene- 21-one and ,β-onoceradienedione. This is the first time that 6α,9β-dihydroxyeudesma-4(15)-ene has been found in nature.