Lupeol, a dietary triterpene, present in fruits and medicinal plants, has been reported to possess pharmacological properties including anticancer activities both in vitro and in vivo. The present study investigates the anti-cancer activity and the underlying mechanisms human mammary cancer (MCF-7). We observed increased levels of antioxidants (ABTS, DPPH, superoxide anions radical scavenging activity and hydroxyl radical scavenging activity) in MCF-7 cell line. The higher concentrations of lupeol analogues significantly increased cytotoxicity in MCF-7 cells. The IC 50 value was found to be 40 µM/mL of lupeol analogue (oxime) could greatly inhibit the cell growth. So, we have chosen at 40 and 320 µM/mL concentration of lupeol analogue (oxime) for further experiments. We observed increased levels of Lipid peroxidation and decreased levels of Antioxidants (SOD, CAT, GPx and GSH) in MCF-7 cell line because of the pro oxidant mechanism of lupeol analogue (oxime). These observations revealed the cytotoxic potential of lupeol, which could be attributed to their pro oxidant property on the MCF-7 cells. It is evident from the observation made in the present study that the lupeol analogue (oxime) has potential anticancer effect compared to Lupeol.