Human protein-energy malnutrition and zinc deficiency have common clinical features. These were related to the plasma zinc concentrations in 42 severely malnourished children. A low plasma zinc concentration was strongly associated with nutritional edema but not with the degree of edema or the plasma albumin concentration. In the absence of edema, there were significant relationships between plasma zinc concentrations and stunting, skin ulceration, and wasting. Infection was not necessarily associated with a lower zinc concentration. From these data, it can be predicted that a malnourished child with edema, skin ulceration, stunting, or severe wasting, will have a low plasma zinc concentration.