Abstract: Objective To study feeding practice,infant temperament and family environment among low birth weight(LBW) infants aged 0-3 and investigate obesity and malnutrition occurring in them at pre-school age,finding their relationships and providing the grounds for reducing obesity and malnutrition among LBW children.Methods A group of 66 LWB children, checked in Putuo District Maternal and Child Care Center and a group of 33 normal children, checked in Putuo District Changshou Community Health Center were investigated by means of questionnaire in relation to feeding,diet,by Carey's "3 to 7-year-old questionnaire "(parent questionnaire) and "Family Environment Questionnaire".Results Family environment and infant temperament were found to be related to obesity occurring in preschool children. Feeding practice for 6-month-old,and family environment were found to be connected with malnutrition occurring in pre-school children.Conclusion The factors raising the rate of obesity and malnutrition occurring in pre-school children are feeding in 6-month-old,infant temperament and family environment. To measure and assess these impact factors for LWB infants is significant to help parents to build health thinking and to know how to feed and how to build a warm family.