Abstract: Objective To explore the prevalence of behavior problems and the related factors among floating children aged 3-6 years old in Pingshan.Methods A stratified cluster sampling method was taken to select 999 floating children aged 3-6 years old in Pingshan. The caregivers of the selected children were surveyed with questionnaires.Results ① Total detection rate of behavior problems was 11.7%. The boy's detection rate (15.4%) was higher than girl's (7.8%). There was a significant gender difference in the detection rate (P<0.01). ② The most prevalent behavior problem was peer problem (27.8%), followed by hyperactivity (19. 4%), prosocial (13.8%), conduct (11.5%) and emotion (8. 5%). ③Girl, older children, a good relationship with father, seldom scolded by mother, the primary caregiver being mother before aged 3, in good health, ever participated in psychological screening were the major protective factors of behavior problem (P<0.05).Conclusions A relative high prevalence of behavior problems among floating children between 3 and 6 years old in Pingshan. Intervention measures are recommended to promote children's mental health.