The cases of 5 children with severe malnutrition, marasmic type, aged four to fourteen months are reported. The patients were sturied at admission in the hospital and 45-60 days and 4-5 months later. Eeach study included: hemoglobinemia, cholesterolemia, glycemia, weight, height, Gesell test, neurological examination, pneumoencephalogram, electroencephalogram and cerebrospinal fluid examination. Biochemical and physical recuperation was very good. Gesell test show an important and homogeneous deficiency, even at the third study. All patients presented cortical atrophy at the pneumoencephalogram in the first study: 4 patients were re-studied 4-5 months later and only one become normal. No changes in electroencephalogram and cerebrospinal fluid were found. It was not possible to evaluate the significancy of the poor psychosocial environment from where the patients came in the aetiology of the mental deficiency.