Breast-feeding is widely believed to be the most beneficial method of feeding for the health and well-being of most infant. Health organizations including the world Health organization (WHO), recommend the breastfeeding exclusively for six months. The aim of this study to determine the prevalence of breast-feeding in Al-Marj area and the associated factors that’s prevent mothers from breast-feeding, cross sectional study done, total of 786 mothers conducted in this study, our results were mostly the same as other studies with some difference, the prevalence of exclusive breast-feeding in the first 6 months [20.74%], lag far behind WHO recommendations. There is a major problem with adequacy of breast milk production in the majority of mothers in this study, which might indicate the need for proper awareness and teaching programs regarding breastfeeding in our community [knowledge more about benefit and practice].