Abstract: From June to July 2009,a typhoid fever outbreak occurred in Guangfu township of Wuzhong district in Suzhou,which involved 98 cases. The outbreak had common source,the cases were mainly distributed in Yuli,Taihu and the town. There was no gender difference on the incidence and the disease occurred in all age group. The majority of the cases were farmers. The water contamination was excluded as the source of the outbreak by the analysis of cases distribution and tap water network direction,environmental water sample detection and case control study. The outbreak was caused by the contaminated food sold by a vender. The outbreak ended after the control measures were taken,