Five new diterpenoids (1-5), five new sesquiterpenoids (6-10), and three known compounds (11-13) were isolated from the roots of Illicium majus. Their structures were elucidated by extensive spectroscopic analysis. The absolute configuration of 1 was assigned by X-ray crystallography, whereas those of the 1,2-diol moieties in 3 and 4 were determined using Snatzke's method. The abietane acids 1, 2, 11, 12, and 13 displayed antiviral activity against the Coxsackie B3 virus, with IC50 values of 3.3-51.7 μM/mL.