Objective To evaluate the effect of vitamin A (Vit A) supplementation on the morbidity and mortality in children with infectious diseases. Methods We searched Cochrane Library (Issue 1, 2004), MEDLINE (1966-2004.3) and The PedsCCM Evidence-Based Journal Club (1992-2002). Relevant systematic reviews and randomized controlled trials (RCTs) of Vit A supplementation on morbidity and mortality in children with infectious diseases were obtained. Results We collected 107 studies and identified 13 systematic reviews or RCTs. The evidence showed that the effect of Vit A supplementation on morbidity and mortality was affected by the nutritional status of the children. Vit A supplementation given to Vit A deficient children could reduce the morbidity of diarrhea and mortality of measles. However, Vit A supplementation would increase the morbidity of diarrhoea and respiratory infections in children with sufficient nutrition. Conclusions The nutritional status of children correlates with morbidity and mortality of some infectious diseases, and the nutritional status and serum Vit A level should be evaluated before Vit A supplementation applied.