Numerous Euphorbia species are used to treat a range of conditions, including warts, intestinal parasites, and skin disorders. Additionally, some species of Euphorbia have long been used as remedies for warts, gonorrhea, migraines, intestinal parasites, and skin conditions. Hence, the present study was conducted with the main purpose of phytochemical screening and evaluation of antioxidant properties aqueous (aq.) extract of stem parts of E. milii. Stem parts of E. milii were selected for phytochemical screening and subjected to successive solvent extraction by continuous hot Soxhlet extraction with double distilled water. Results revealed that the major phytochemicals found in aq. stem extract of E. milii were found to be steroids/phytosterols, anthocyanin and betacyanin, terpenoids, flavonoids and tannins. The IC50 values exhibited by aq. stem extract of E. milii was found to be 124.53 µg/mL. In conclusion, this preliminary study showed that the stem parts of E. milii have a variety of secondary metabolites in their aqueous extract. Based on biological activity like antioxidant properties of aqueous extract of E. milii stem parts, it is possible to use E. milii as a potential drug agent for traditional medicines. Furthermore, it is advised that more research be done to clarify the precise mode of action of the different secondary metabolites found in E. milii against different illnesses.