Abstract： Objective To determine 11 kinds of pathogenic microorganisms related with human infectious diarrhea,and prepare biochips to detect pathogenic bacteria in stool samples of diarrhea patients in outpatient clinic.Methods According to the data of pathogenic bacteria detection in stool samples in diarrhea clinics of our hospital between Jan uary 2009 to December 2012,bioinformatic method was used for collecting whole sequences of 11 species of pathogenic bacteria,designing primers and probes,optimizing and preparing chips.PCR experiments were performed and amplification results were analyszd.The specificity of these chips was evaluated by detecting 163 strains of intestinal bacteria isolated from diarrhea patients,and sensitivity of chips was accessed by detecting stool samples mixed with different concentrations of Salmonella.1 052 stool samples were collected from diarrhea patients from June 2010 to March 2013 in our hospital.PCR,bacterial culture and DNA microarray chip were performed on these samples in order to compare the positive rates of different detection methods.Results Detection chips of 11 kinds of diarrheaassociated pathogens were successfully prepared.The accuracy rate 163 of clinical isolated strains detected by these chips was 100％.When Salmonella was detected,sensitivity of chips was 102 CFU/ml,which was 10 times greater than the PCR assay.The positive tate of 1 052 clinical diarrheal samples was tested by these chips was 36％,better than that of the traditional bacteria culture and PCR assay,which was 13％ higher than that of traditional bacteria culture (x2=2.28,P＜0.05) and 4％ higher thanthat of PCR assay (x2=5.16,P＞ 0.05).Conclusions Microarray chips of 11 kinds of diarrhea-associated pathogens is successfully prepared,which can detect 11 kinds of pathogenic bacteria of diarrhea simultaneously,with good specificity and sensitivity,and higher positive.This method can be used in clinical practice.