Abstract: Abstract: The antibacterial activies and efficacy of Taurolidine against mixed infection with Escherichia coli and Salmonella in chickens was carried out. By means of 2-fold diluent method, the MIC of antibacterial activies of Taurolidine were obtained. One hundred eighty of four-day old chickens were randomly devidedinto eight groups: I was uninfected and unmedicated control, II was infected and unmedicated control, III was Florfenicol treatment group, IV,V,VI were Taurolidine treatment groups with high, moderate and low dose, respectively. Compared with infected and unmedicated group, the died rate of high dose and moderate dose of Taurolidine group was reduced 20.0%,16.7%, respectively. The healing rate of high dose and moderate dose of Taurolidine group was increased 23.3% and 16.6%, respectively. The effectiveness and healing rate of high dose and moderate dose of Taurolidine was better than Florfenicol group. The MIC of antibacterial activies of Taurolidine against Escherichia coli and Salmonella was not lower than 256 μg/mL. The results showed that Taurolidine has certain efficacy against mixed infection with Escherichia coli and Salmonella.