Aimed to analyze the main factors in the perception of nursing, which interfere with exclusive breastfeeding for the first six months of life infant. Was conducted a descriptive study with a qualitative approach, data were analyzed using a technique of Content Analysis. The central theme identified: Elements that interfere with exclusive breastfeeding from the perspective of mothers. The elements involved were identified: breast problems, the fact that be an intense practice, too much housework, other children to look, the work out of his home and especially the popular beliefs and practices of mothers and their families, as fact that "milk is weak, and not just support" and the need to offer other foods, water and teas. It is of utmost importance not to generalize the ability to breast-feed without first considering the context in which the mothers and infants are inserted.