Abstract: Phytochemical analysis of foliage of Pupalia lappacea (L.) Juss (Amaranthaceae) afforded 8 compounds, namely; 1-docosanol, stearic acid, stigmasterol, -sitosterol, N-benzoyl-L-phenylalaninol acetate, -sitosterol-3-O- -D-glucopyranoside, stigmasterol-3-O- -D-glucopyranoside and 20-hydroxyecdysone. The ecdysteroid, 20-hydroxyecdysone, constitutes nearly 0.3% of the dry weight and 13% of the dichloromethane extracts of the plant, making Pupalia lappacea a probable commercial source for this important ecdysteroid. Both the hexane and dichloromethane extracts showed significant antioxidant activity with the dichloromethane exhibiting an IC50 comparable to that of BHT, a synthetic antioxidant. All the isolated compounds are reported for the first time in the genus.