Eco-physiological study was made on three highly economic three weeds growing in the rural areas of the Nile Delta. Plant samples (leaves and stems) in addition to soil samples were collected from five different sites. Functional plant traits were studied extensively in relation to soil variables. On the basis of the results of this study, extracts of the studied weedy species have significant antioxidant activity compared to other, well characterized, standard antioxidant systems in vitro. The production of phenolic compounds in the studied weeds are promising as a rich source of natural antioxidants, food supplement and pharmaceutical industry.