Objective To explore the related factors of school refusal behavior in child and adolescent.Methods Investigated 141 students who had school refusal behavior in the department of psychiatry as the case group. 109 students were chosen randomly from 3 different grades in different schools as the control group. Two experienced psychiatrists made diagnosis according to DSM-Ⅳ criteria, the case group completed the direct factor investigation of School Refusal and the general condition questionnaires. The control group completed the general condition questionnaire only. Results 61 (43.7%) of the case group were diagnosed mental disorder according to DSM-Ⅳ ,17(28.91% ) of them were diagnosed mood disorder, which was the most in all kinds of mental disorder in case group. The results showed that age (P = 0.0003 ), location (P = 0. 035 ) and family income (P ＜ 0. 01 )were the most important factors for school refusal behavior in child and adolescent. The opinions of child and parent on the school refusal factors were quite different (P ＜ 0. 05 ). The former three direct reasons of school refusal were study pressure (6.47%) ,much more examinations and homework( 6.03% ) ,and willing to stay at home only (5.63%). Conclusion Mental disorder is the main causation of school refusal behavior. Age, location and family income are related closely to school refusal behavior. Study pressure, peer difficulty and poor parent-child relationship are direct factors of school refusal behavior.