Abstract: In order to define the main pathogen caused postharvest brown rot of late-ripening peach and control effect of antagonistic bacteria,"Yingshuanghong" late-ripening peaches were used as the test materials. Then traditional morphological methods and 18S-rDNA molecular biology method was used to identify the pathogen caused postharvest brown rot of late-ripening peach. At the same time,four kinds of antagonistic bacteria were used to prevent postharvest brown rot of late-ripening peach. Results showed that,in this study,pathogen separated from brown rot of late-ripening peach belongs to fungi,Ascomycota,Ascomycetes,Helotiales,Sclerotiniaceae,Sclerotinia and the fungi injury incidence was 100%. The inhibition effect of four kinds of Bacillus B001,B1,HB-2,and B579 to brown rot disease was significant. The inhibitory effect of B001 and B579 ahead of 1 d or 2 d prevention treatment was inhibitory effect significantly higher than 0 d treatment(p<0.05). The inhibitory effect of B1 and HB-2 ahead of 1 d prevention treatment was significantly higher than the other two groups(p<0.05). At the same time,the four kinds of antagonistic bacteria,a certain extent,could inhibit the decrease of V_C content,soluble solids content,titratable acid content and hardness of late-ripening peach. The antagonistic bacteria,which in biological control of postharvest brown rot of late-ripening peach,has good application potential.