Objective   To explore influence factors of childhood simple obesity(CSO)among school age children.

  Methods   Amultiple stage stratified cluster sampling was conducted among 8 primary schools, grade 1~5 in Xuzhou.The available data were analy zed by mono-factorial and mult-i factorial no conditional log istic reg ression using SPSS1.15 softw are.

  Results   8 risk factors were identified for CSO in multiple-reg ression model at P=0.05 level, they were obesity of parent, overweightto be born and one year, no good behavior of drinking and eating; 4 exposure factors were protective for CSO, they were reasonable feeding style after born one year and exercise.There were fairly larger values of OR among classes involving factors of birth weight, body weig htof one year, speed of eating, liking flesh, main appetite of grain and exercise.

  Conclusion   Influence factors on CSO of school age children in Xuzhou are nutrition surplus, deviation on behavior of drinking and eating.Parents, school and communities should create a social circumstance to inter fere for CSO.