Abstract: Objective To explore juvenile offender's mental health,their personality character istics and the influence on mental health.Methods 170 juvenile offenders were investigated in group by general questionnaire,Eysenck Personality Questionnairr(EPQ),and SCL-90,and 180 college students,middle school studenls and pupiles were chosen as normal controls.Results The juvenile effenders showed significantly higher scores of neuroticism(N)and psy choticism(P)subscales of EPQ,lower scores of extroversion(E)subscale and lie(L)subscale.The differences in seven subscales compulsive symptoms,heavy heartedness,anxiety,hostility,paranoid,mood disorders between the juvenile offender and the controll students were of statistical singnifieance(P<0.01).The juvenile offenders.scores of neuroticisism(N),and psy choticism(P)were significantly related to their mental health(P<0.01).Conclusion The mental health of juvenile offenders tends to be away from the normal,and the mental health is not good and their personality characteristics influence their mental returning.