To investigate the therapeutic effects of florfenicol combinate TMP against E.coli bacillosis in chickens,The drug with part efficacy on local E.coli bacillosis was as negative control group.The infected chickens,florfenical,enrofloxacin and florfenicol combinate TMP groups were positive groups.Contrastive treatment results showed that combination group(50 ug/mL) was the best.The dispensing ration is(5∶1,)and the concentration of florfenicol is 42 ug/mL,TMP is 8 ug/mL.