In this review, I describe the effect of breastfeeding in premenopausal breast cancer in Jordan. For the time being, breast cancer is considered to be the most frequent type of cancer among women in the world. Many studies explore the effect of breastfeeding to prevent of breast cancer, although studies have suggested that breastfeeding reduces the risk of breast cancer. In 2020, 2.3 million women diagnosed with breast cancer and 685 000 deaths in breast cancer in the world. In the end of 2020, there were 7.8 million women alive who were diagnosed with breast cancer in the past 5 years, making it the world’s most prevalent cancer (WHO, 2021). mothers should be encouraged to breastfeed their babies because the clinical evidence has shown that there is a lower risk of breast cancer in women who breastfed their babies.