Abstract: In order to investigate the control effects of fermented broth of Bacillus strains and volatile organic compounds against postharvest Alternaria alternata of the"JinLiuZaoHong"super-early maturing peach, the injury inoculation method, post-harvest soaking method and plate-to-plate method were studied. The antibacterial activity and the effect of three Bacillus strains HB-2, B1 and X on postharvest quality of super-early maturing peach, and the antibacterial activity of volatile organic compounds of fermented broth was analyzed by the two-sealed-base-plates method and headspace solidphase microextraction combined with gas chromatography-mass spectrometry (SPME-GC-MS) method. The results showed that fermented broth of three Bacillus strains could significantly inhibit the colonization growth of Alternaria alternata (p<0.05) compared with the control group, and they also significantly delayed the decreasing of vitamin C contents, titratable acid contents and firmness and maintained quality, with the order of HB-2>X>B1.In addition, the volatile organic compound sproduced by three Bacillus strains fermented broth had significant inhibitory effect on the expansion of Alternaria alternata colonies with the inhibitory rate reached above 50%, and 28, 31 and 30 kinds of compounds were identified in HB-2, B1 and X, respectively, such as alcohols, esters, ketones, acids, phenols, alkanes and so on. Bacillus HB-2, B1 and X would have potential application for the biological control of postharvest diseases of super-early maturing peach.