The invention discloses a polyoxins-containing bactericidal composition which contains A and B, wherein the A is selected from polyoxins, the B is selected from any one of the following bactericides: ethirimol, JS399-19, bromothalonil, zineb, chlorothalonil and dithianon, and the weight ratio of the active components A and B is 32:1-1:64. The polyoxins-containing bactericidal composition can prevent and treat various crop diseases, has an obvious synergistic effect, enlarges the bactericidal spectrum, and has relatively high activities to diseases such as downy mildew, epidemic diseases, anthracnose, powdery mildew, leaf spot disease, gibberellic disease, rice blast, and the like; and the pesticide dosage is reduced, the residues of pesticides in crops are reduced, and the environment pollution is reduced.