Objective: To explore the emotional and behavioral problems of floating adolescents with the experience of being separated from their parents. Methods: Totally 821 floating adolescents with the experience of being separated from their parents for more than 6 months were classified to separated group, 781 floating adolescents without the experience of being separated from their parents were classified to control group. All of them were asked to complete the self-made questionnaires, the Strengths and Difficulties Questionnaire (SDQ), Security Questionnaire ( SQ). Results: The SDQ total scores [ (13. 8 +/- 5. 2) vs. (12. 3 +/- 4.9), P < 0.001 ] and its factor scores of emotional symptoms, behavioral problems and hyperactivity were higher in the separated group than in the control group. There were no significant differences on the scores of peer relationship problems and pro-social behaviors between die two groups (P > 0.05). The SQ total scores [(53.1 +/- 11.8) vs. (55.9 +/- 11.4), P < 0.001] and scores of two subscales (Ps <0.05) were lower in the separated group than in the control group. Linear regression models showed that, in the separated group, less total difficulties were negatively associated with higher secure level (beta = - 0.25) and mother care-giving (beta = -2.42), while positively associated with separated from father-only (p = 2.38). Pro-social behavior were positively associated with secure level and being girls (beta = 0.91,0.02). Conclusion: Floating children with the experience of being separated from their parents may be at greater risk to develop more mental health problems and less security level.