Objective:To explore the relationship between the Bifidobacterium in neonatal intestines and the occurrence of diarrhea in its infancy in order to provide an evidence for prevention of infantile diarrhea.Methods:The Bifidobacterium from the cultured feces were counted in every neonates.The less sufficient count of Bifidobacterium was less than 7.0(LgN/g)

while the sufficient count of Bifidobacterium was at least 7.0(LgN/g).There were 4 groups(group A

B

C and D)in this study

and there were 30 neonates in each group.The Bifidobacterium count in group A and B was less than 7.0(LgN/g).The Bifidobacterium count in group C and D was at least 7.0(LgN/g).The exogenous Bifidobacterium was administrated to the neonates in group A and group C.Their occurrence of diarrhea was followed up for 1 year.Results:The incidence of diarrhea (including infective diarrhea) was lower in the infant whose Bifidobacterium count was sufficient.The administration with exogenous Bifidobacterium in the early neonatal period could reduce the incidence of infant diarrhea significantly.Conclusion:The Bifidobacterium in neonatal intestines is related to occurrence of diarrhea in its infancy. The administration with the exogenous Bifidobacterium in the early neonatal period can reduce the incidence of infantile diarrhea.