The features of crimes, their causes and backgrounds of 70 army delinquents, comparing with the controls, were studied from Nov. 1st, 1976 to Nov. 20, 1976 The results were as follows: 1. Most of the delinquents were from the adverse circumstances i. e. low education level, poor economic status, farmers and had got married. 2. The majority of the delinquents occurred within the first 2 years of the enlistment. 3. The rate of the parent-loss of the criminals was definitely higher than that of the controls. (48.6%) 4. Escapers from military service were over the half of them, and violence, steal and embezzlement were followed. The motivations of the escape from the military service was mostly domestic problem and illness; but a lot of the criminals also escaped for amusement and pleasure. 5. The prognosis of them was relatively favorable and constructive.