This article presents trends of breastfeeding in Spain from the 1960s to the end of the century, analyzing the relationship between level of education and breastfeeding duration. A sample of 666 adult women provided data about breastfeeding practices for children born between 1958 and 2002. Joinpoint regression models for breastfeeding duration for the firstborn child throughout these years show a U-shaped curve, with a sharp decrease at the beginning of the 1970s (-17.2%) and a gradual increase toward the end of the century (1.9%). However, the trend for women with primary studies shows a constant decrease throughout the whole period (-7.4%), while higher education levels relate to a positive trend from the 1970s onward (3.4%). The authors conclude that in the Spanish context, maternal level of education is not associated with breastfeeding duration in the same direction or with the same magnitude across time. Factors related to breastfeeding should be studied, taking into account social context.