Background: Regardless of enormous efforts, only 17% of Vietnamese newborns are exclusively breastfed during the first six month, respectively. Objective: To determine the relation between correct knowledge of breastfeeding before hospital discharge and practice of exclusive breastfeeding at one month postpartum. Method: A prospective cohort study was carried out at Hung Vương hospital, a tertiary-level ObGyn Hospital of Ho Chi Minh City from January to may 2010.