Objective To explore the relationship between perceived social support,pro-social behavior and self-esteem of children affected by AIDS,and provide a theoretical basis for the children affected by AIDS to establish good pro-social behavior.Methods 300 children affected by AIDS were taken from Henan province where seriously affected by HIV.Perceive social support scale,self-esteem scale and pro-social behavior scale were used to test the 300 children affected by AIDS.Multiple linear regression analysis,bootstrap testing and other statistical analysis were used for data correlation analysis.Results (1) Children affected by AIDS perceived social support effects are significantly positively related to their self-esteem(r=0.436,P＜0.01) and pro-social behavior(r=0.457,P＜0.01).Children affected by AIDS self-esteem was significantly positively related to pro-social behavior (r=0.477,P＜0.01).(2)The variance of the interpretation of the mutation rate of perceived social support to the pro-social behavior of children affected by AIDS was 20.8％ (F=67.944,P＜0.01).The variance of the interpretation of the mutation rate of self-esteem to the pro-social behavior of children affected by AIDS was 22.8％ (F=76.146,P＜0.01).(3)Self-esteem as an intermediary variable,perceived social support of children affected by AIDS were significantly for both direct effect and indirect effect.The estimation value of the self-esteem's mediating effect was 0.208(P＜0.01) and the estimation value of direct effect between perceived social support and pro-social behavior was 0.272(P=0.02).Conclusion Perceived social support and self-esteem are the chief influencing factors of pro-social behavior of the children affected by AIDS.Self-esteem is the mediator of perceived social support and pro-social behavior.