Screening and development of bacterial strains with biocontrol effects against early blight of potato, to provide strain resources and basis for effective prevention and control of this disease. Bacteria with obvious antagonistic effects were isolated and screened from the rhizosphere soil of potato early blight diseased plants as the tested strains. As a result, an antagonistic strain WB-1 with an inhibition rate of 76% against the target pathogen was screened out. The colony shape was light yellow, with regular edges, nearly round, slightly convex, moist and smooth, opaque, and rod-shaped. The ends are blunt and rounded. After 16S rDNA and gyrB gene sequence analysis, the homology with Bacillus velezensis（LC506620.1） and B. velezensis（MN365038.1） was 71% and 95%, respectively. After identification, the strain WB-1 is B. velezensis. It has the ability to dissolve inorganic phosphorus, produce indoleaceticacid（IAA） and siderophores. The pot experiment results showed that the strain WB-1 can significantly reduce the disease index of potato early blight, with a relative control effect of 69.26%. Therefore, the biocontrol strain WB-1 obtained in this experiment has a good inhibitory effect on potato early blight and can be used as a candidate strain for preventing and controlling potato early blight.