Menopause is the permanent end of menstruation and fertility. It is a natural process and not a disease. Menopause can lead to a decrease in estrogen production. Estrogen, an immune-modulating hormone is associated with proper functioning of the immune system. Oxidative stress is defined as an imbalance between production of free radicals and reactive metabolites. Normally, antioxidants neutralize ROS and thus help to prevent over exposure from oxidative stress. The association of this increase in serum GGT with enhanced oxidative stress and reduced antioxidant defense system in the post-menopausal women may lead to the speculation that GGT could be considered an index or a marker of oxidative stress. Objective: To measure the Oxidative Stress and estrogen (Estradiol) in pre- and post-menopausal woman and correlate it with the level of enzymatic markers Gamma glutamyl transferase (GGT) in serum with the amount of oxidative stress in pre- and post-menopausal women. Material and Method: The study was carried out in the Department of Biochemistry, NIMS Medical College and Hospital, Shobha Nagar, Jaipur, Rajasthan. A total of 100 patients attending Obs-Gynaecology OPD were taken, out of which 50 were Post-menopausal women and 50 were Pre-menopausal women. Results: The level of oxidative stress was high in post-menopausal female as compared to pre-menopausal female. The level of Gamma glutamyl transferase (GGT) was higher in postmenopausal women as compared to premenopausal women. The level of hormone estradiol in postmenopausal women is lower than the premenopausal women indicating that oxidative stress decreases the level of antioxidant property of estrogen hormone (Estradiol). The study highlights the role of Gamma GT as an indicator of oxidative stress.