The problem of juvenile delinquency is now managed by welfare or judicial institutions and not by medical practitioners in the field of child psychiatry. Therefore the problem is mainly discussed sociologically and psychologically, and not clinically from the standpoint of child psychiatry. Clinical classification of juvenile delinquents is necessary for their diagnosis and treatment in terms of the analysis of their behavior and criminality. Family research and Rorschach tests were performed, and four types of juvenile delinquents were defined. Those of the first type, which characteristically undergo early socialization and look for an identifying object in their group, have broken families with economic problems. The second type, which is unadaptable and dependent on the group mind, has over-protective parents. The third type, which takes on a counter identity, shows substantial broken family relations and poverty. The fourth type, which is asocial and acts out obsessively with hard conflict, reflects the mother's own problems. The CNV test was also employed. It seems that central nervous dysfunction plays an important part directly or indirectly in juvenile delinquency. From the developmental point of view, the first type of juvenile delinquent is considered to have a passing disorder of the later 2nd individuation process which I have proposed here. Also the second type one of the earlier 2nd individuation process, the third type one of the 1st grouping and individuation process and the fourth type one of the 1st individuation process. The problem of juvenile delinquency was discussed in relation to other asocial problems in child psychiatry in relation to the classification and developmental process.