A new flavone, 6-methoxy-7,8-dihydroxyflavone (1), and a new natural flavone, 7-methoxy-6,8 dihydroxyflavone (2), together with two known flavones wogonin (3) and oroxylin A (4), were isolated from Tridax procumbens. The structures of the compounds were established on the basis of 1D and 2D NMR data and HR-ESI-MS data interpretation, as well as by comparison with known analogs in the literature. All the compounds were evaluated for their antioxidant capabilities in vitro using 1,1′-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assays. Compound 1 (EC50 = 21.75 μg/mL) exhibited the most potent antioxidant activity.