Five terpenes (1~5), three fatty acids (6~8), two sterols (9 and 11), and a monogalactosyldiacyl glycerol (10) were isolated from the methylene chloride extract of the aerial part of Cirsium setidens. Their chemical structures were determined to be $alpha$-tocopherol (1), 25-hydroperoxycycloart-23-en-3$eta$-o1 (2), 24-hydroperoxycycloart-25-en-3$eta$-o1 (3), mokko lactone (4), transphytol (5), 9, 12, 15-octadecatrienoic acid (6), 9, 12-octadecadienoic acid (7), hexadecanoic acid (8), acylglycosyl $eta$-sitosterol (9), (2R)-1, 2-O-(9z, 12z, 15z-dioctadecatrienoyl)-3-O-$eta$-D-galactopyranosyl glycerol (10) and $eta$-sitosterol glucoside (11) by spectral evidences. Compound 3 exhibited significant cytotoxic activity against five human cancer cell lines with its $ED_{50}$ values ranging from 2.66 to 11.25 $mu$M.