We studied psychosexual development in 28 adolescent males who had survived leukemia and compared it with that in 25 adolescent males who had survived other malignancies in childhood. A clinical semistructured psychiatric interview was used to form 8 criteria of psychosexual development. Sexual identity was also assessed using a psychological test. By every criterion, development was more disturbed in patients who had survived leukemia. Attitudes toward adult-type genital sexuality, contact ability with the opposite sex, and the developmental level of sexuality were most significantly affected.