In this study, a cluster random sampling method was adopted, and a total of 322 students from freshman to junior college of public security police were investigated by symptom self-rating scale (SCL- 90) and Eysenck Personality Questionnaire (adult version) (EPQ). The following conclusions were drawn: The scores of somatization and other factors in the symptom self-rating scale were lower than the national norm. Gender, grade, source, category and other factors have a significant impact on the mental health of public security police trainees; The average score of male public security police students in interpersonal sensitivity is significantly higher than that of female students, while the average score of female students in compulsion factor is significantly higher than that of male students. The public security police trainees are mainly intermediate in the three characteristics of spiritual quality, internal and external orientation and concealment. The neuroticism is dominated by the typical type. The freshman public security police students have fluctuating emotions, and they are prone to intense emotions when things happen. In the adult version of Eysenck personality questionnaire (Eysenck), neuroticism has a positive predictive effect on the mental health level of public security police trainees, while the internal and external dimension (E) and the masking dimension (L) of EPQ have a negative predictive effect on the mental health of public security police trainees.