AbstractThis work aimed at assessing the phenolic content, antioxidant and cytotoxicity capacities of methanol extracts obtained fromTagetes minuta,Euphorbia granulataandGalinsoga parvifloramedicinal plants. Standard spectrophotometric and chromatographic methods were used for chemical analysis. Established antioxidant and cytotoxicity assays were adopted for biological activity assessment. In silico screening for the individual phenolic acids was performed using molecular docking techniques.E. granulatashowed a significantly high level of polyphenols. Highest level of flavonoid and tannin contents were detected inGalinsoga parviflora. Ten phenolic acids were identified and quantified via GC–MS in all extracts, and p-Hydroxybenzoic was the most dominant acid (70 µg/g) inT. minutawhile gallic was the predominant acid (73 µg/g) inE. granulata. Extracts showed higher reactive oxygen and nitrogen species scavenging activities and exhibited lower hydrogen peroxide inhibition values. The strongest cytotoxic activity was exhibited byT. minutaextract on A2780 cell line. The cytotoxic activity ofG. parvifloraextract was highly significant against all cancer cells. Extract ofE. granulatashowed best activity towards MCF7 and A2780 cell lines and was less active against HT29 cell line. In silico data revealed that caffeic acid had the lowest value of binding energy and high ligand efficiency ratios against the selected target receptors, comparable to the standards. Methanol extracts of the targeted plants showed promising antioxidant and anticancer activities which could be attributed to presence of different phenolic phytochemicals. Further work is required for determining the active compounds and their mode of action.