A case-control study of children attending a diarrhoea treatment unit (DTU) in Calabar, Nigeria was undertaken to evaluate the association between failure to breastfeed on one hand, and dysentery, persistent diarrhoea and malnutrition on the other. The prevalence of dysentery, persistent diarrhoea and underweight were 6.3%, 1.2% and 36.4% respectively among a total of 1133 children with diarrhoea. The proportion of the children with persistent diarrhoea or underweight was significantly lower among currently breastfeeding children than the age-matched, non-breastfeeding counterparts (p< 0.05). Dysentery was also less frequent among breastfeeding children (5.8%) than the non-breastfeeding ones (7.4%), but this did not reach statistical significance. The findings lend support to the enormous benefit of breastfeeding as a child survival strategy. Global efforts geared towards the support of breastfeeding should be intensified especially the less developed countries where diarrhoea-related morbidity and mortality constitute a major public health problem.