Objective To comfirm the importance of WHO"warm chain" by investigating neonatal body temperature after birth.Methods Axillary temperatures of 302 neonates born in our hospital in spring,summer and winter of 1995 were monitored immediately after cord ceased and 1,2,4,6,8,10,12,14,16,18,20,22,24,48,and 72 hours after birth.The incidence of low body tem- perature in each time was calculated.Resultes The time after birth that average body temperature need to reach 36.5℃ was ten hours in spring,14 hours in summer and winter.The incidence of low body temperature at 2 hours after birth in summer was 95 %,at 6 hours in winter was 97%.The in- cidence of low body temperature at 72 hours were still 16% in spring,34.1% in summer and 27.7% in winter respectively.Conclusion Key point in carrying out"warm chain"is to enhance the re- sponsibility of medical staff not only in rural hospitals,but also in urban hospitals.