Antrodia camphorata is a rare and valuable medicinal mushroom. In this work, 11 new triterpenoids, namely, antcamphorols A-K (1-11), together with 10 known triterpenoids, 12-21, were isolated from dish-cultured A. camphorata. Compound 1 is an unprecedented C lanostane-type triterpenoid featuring a methyl group at C-15 and a C-21-O-C-24 tetrahydropyran ring at C-17. Compounds 2-11 are ergostane-type triterpenoids, and they include two pairs of norergostanes 2-5. The structures of the new compounds were identified by NMR, 2D NMR, and HRESIMS data analyses. The absolute configurations of 1 and 6 were defined by X-ray diffraction data, and the absolute configuration at C-25 of 4 was determined by the modified Mosher's method. Compounds 7, 9, 10, 16, and 19 showed significant ROS scavenging activities (63.9-70.5% at 20 μM) in high-glucose-induced HUVECs. Compounds 3 and 8 exhibited moderate cytotoxic activities against U251 (IC, 9.2 μM) and MCF-7 (IC, 8.1 μM) human cancer cell lines, respectively.