The purpose of this study was to find the difference and relationship between high sc hoof students` self-identity and delinquency impulsivity. The subject of this study were 392 students(lst and 3rd grade of 4 high schools in Keochang). Self-identity test devise d from questionnaire of Korean type-self-identity constructed in 1996 by Mr. Park and questionnaire of delinquency impulsivity written by Mr. Lee in reference to Mr. Jung`s Personality Test for Elementary students and Mr. Lee`s standardized Diagnostic Test of Personality was used, which was amended and revised with the help of Mr. kim in acco rd with the level of high school students. The results of this study were as follows First, academic students had higher scores than vocational, and first grade students, third grade, in levels of self-identity, but there is no difference between male and female students. Second, vocational students had higher scores than academic, and third grade students, first grade in delinquency impulsivity, but there is no difference between male and female students. Third, there is a certain anti-relationship between self-identity and delinquency impulsivity, and in case of subarea, there is a certain relationship in realms of autonomy, self-acceptance, goal-aiming, leading, and intimacy.