Abstract :Epidemiological and dietary intervention studies in animals and humans have suggested that bioflavonoids such as quercetin plays a beneficial role in inhibiting, reversing or retarding tumorigenesis in prostate and breast cancer. Quercetin 3,31,41,5,7 – pentahydroxyflavone a naturally occurring flavonoid, is a component of most edible fruits and vegetables with the highest concentrations being found in onions, apples and red wine [1]. Quercetin has a broad range of pharmacological properties that include antioxidant, anticancer and anti-inflammatory activities [2].