Abstract: Objective The present study was conducted to get all insight into the incidence，epidemiological features and changing trend of diarrhea in Xian and probe into strategies for prevention and control of the disease．Methods Samples of feces were collected with anal swabs from cases of acute diarrhea as attenders of five sentinel surveillance hospitals in the city of Xian．After proliferation，samples were respectively cultivated in four kinds of culture mediums (Alkaline peptone water，SS，EMB and China Blue) to detect V．Cholera，Salmonella，Shigellae and pathogenic E．Coli．Results Among five sentinel surveillance hospitals on diarrhea，the numbers of feces samples and positive rates were not equal with high and low ones．Among detected positive isolates，81.0％ were Shigellae and others were Salmonella and enterotoxigenic E．Coli．Conclusion V．Cholera was not detected among those positive isolates which were mainly Shigellae in 2005．