Two new triterpenoids, vistriterpenoids A (1) and B (2), and four known ones, were acquired from Dodonaea viscosa. Compounds 1 and 2 represent the 24-nor-oleanane triterpenoids isolated from the genus Dodonaea for the first time. Their structures were identified based on extensive spectroscopic methods. Compounds 1, 2, 5, and 6 exerted inhibitory activities against PTP1B in vitro.