Objective To investigate the clinical connection and the incidence of the disease of the infant antibiotic associated diarrhea.Further discuss the affect of the course of diarrhea for used antibiotic.Proposes the preventive measure.Methods Used the review investigate methods.The clinical dates of 112 cases of patients of antibiotic associated diarrhea recently two years in our hospital were analyzed round the time relation of antibiotic use and the diarrhea.Results The period of use antibiotic ≥5 days,the formation rate of diarrhea was increased obviously.The period of use antibiotic longer,the course of disease of diarrhea longer and used more kinds of antibiotics,the formation rates of diarrhea were higher.Conclusion Reasonable use antibiotic and control the broad-spectrum antibiotic use strictly are the linchpin measure to prevent and control the antibiotic associated diarrhea.