Three carotane-type sesquiterpenoids, schisanwilsonenes A (1), B (2), and C (3), were isolated from the fruits of Schisandra wilsoniana. Their structures and relative configurations were elucidated on the basis of spectroscopic methods including 2D-NMR techniques, and the structure of 1 was confirmed by a single-crystal X-ray diffraction experiment. Schisanwilsonene A, at 50 microg/mL, exhibited antiviral activity, inhibiting HBsAg and HBeAg secretion by 76.5% and 28.9%.