As part of our ongoing study focused on the discovery of antioxidants from natural products by measuring the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity, methanol extract of flowers of Carthamustinctorius L. was found to show potent antioxidant activity. Activity-guided fractionation of the methanol extract lead to the isolation of twenty compounds including two flavonol glycosides, quercertin-3-O-β-D-glucopyranoside (12) and kaempferol 3-O-α-L-rhamnopyranosyl-β-D-glucopyranoside (18), two flavanone glycosides, (2S)-4',5,6,7-tetrahydroxyflavanone 6-O-β-D-glucopyranoside (15) and (2R)-5,7,8',4-tetrahydroxyflavanone 8-O-β-D-glucopyranoside (16), and two acetylenic glycosides, 8Z-decaene-4,6-diyne-1-O-β-D-glucopyranoside (13) and 4,6-decadiyne-1-O-β-D-glucopyranoside (14). Their chemical structures were identified by using spectroscopic analysis. Among them, compounds 12-18 were tested in DPPH assay. Compounds 13-16 were first reported to their antioxidant activity. Quercertin-3-O-β-D-glucopyranoside (12) showed the most potent inhibitory effect on DPPH with IC_50 value of 56.7 μM.