Objective To explore the relationship between MP and HSP.Methods The HSP children treated in our hospital during 2004 to 2006 were tested with MP,and the positive patients were treated with the anti-infectious methods.Results (1)The positive rate of MP was 24.14%.(2)By treating with the anti-infectious methods,all positive patients recovered.All syndrome of the patients disappeared in 3 weeks.The mean time in hospital Was (18.9±3.3)days.Conclusion MP infection Was one of the risk factors tIlat might cauge HSP.