Three flavonoid compounds have been isolated from the leaves of Macaranga gigantea (Euphorbiaceae) namely as glyasperin A (1), broussoflavonol F (2), apigenin (3). Their structures were elucidated by spectroscopic methods including UV, IR, HRESIMS, 1D and 2D NMR analysis. Compounds 1–3 were evaluated for their radical scavenging against 2,2-diphenyl-1-picrylhydrazyl (DPPH), showing their IC50 were 125.10, 708.54, and 518.01 μM, respectively. The results indicate that as glyasperin A (1) more active than ascorbic acid (329.01 μM).