Objective To study the personality characteristics of Chongqing pupils and the influencing factors. Methods A cross-sectional survey with Eysenck Personality Questionnaire (EPQ, Children’s Version) and Social Support Rating Scales was carried out to investigate 1 110 pupils in Grade 4 to 6 from 7 schools in Chongqing who were selected by means of cluster sampling. Then the score of each EPQ factor was compared with the norm, and the major influencing factors were screened. Results a) The score of each EPQ factor was compared with the national norm. The scores of the introversion and extroversion, and psychoticism in both gender groups aged 9 to 12, the concealment tendency in the girl group aged 9 to 11, and the neuroticism in both gender groups aged above 11, the boy group aged 9 to 10, and the girl group aged above 12 were all lower than those of the norms (Plt;0.05), but the scores of the concealment tendency in the boy groups aged above 9 and above 11, and in the girl group aged above 12 were higher than those of the norms (Plt;0.05); b) The introversion and extroversion were influenced by the factors of residence, grade, family quarrel, praise and encouragement from parents, being praised by teachers in charge, subjective support and the degree of using support. The neuroticism was influenced by the factors of family quarrel, pressure of homework from parents, praise and encouragement from parents, beating and scolding by family, burden of study, and the degree of using support. The psychoticism was influenced by the factors of gender, residence, one-child family nurture, praise and encouragement from parents, beating and scolding by family, criticism by teachers in charge, burden of study, objective support, and the degree of using support. The concealment tendency was influenced by the factors of gender, grade, family quarrel, pressure of homework from parents, praise from teachers in charge, burden of study, subjective support, and the degree of using support. Conclusion The personality characteristics of pupils in Chongqing tend to be introversion and stability in general, which are influenced by various factors such as individual, family and school.