The experimental bacteria were collected from the suspected Escherichia coli in the heart, liver and lungs of a dead chicken in Jinhua No.9 Pier Chicken Farm. Isolation and identification, biochemical test, pathogenicity test and drug sensitivity test were carried out on the pathogen. The results showed that the pathogen causing the chicken disease was Escherichia coli, which was highly pathogenic and resistant to gentamicin, kanatoxin, doxycycline, chloramphenicol and clindamycin. The results showed that the pathogenic Escherichia coli in chickens showed drug resistance. After using antibiotics in poultry production and when using drugs to treat colibacillosis, sensitive drugs should be selected according to the results of drug sensitivity test, and attention should be paid to replacing drugs and treating according to strategies.