The electroencephalographic tests of 60 juvenile delinquent subjects showed that in 50 percent of the cases the results were abnormal, with varying pathological changes. Pneumoencephalographic tests of 18 of the cases showed changes in 10 of them, mainly dilation and asymmetry of the lateral ventricles. In addition, 20 percent of the subjects showed signs of the organic damage to the central nervous system. The above results indicate that complex investigations of delinquent adolescents are needed. Statistical and tabular data, description of 2 sample cases, discussion of the relevant literature, and references (36 entries) are included. --in Polish.