An antagonistic strain Bacillus subtilis produces large amount of antifungal substance with strong inhibiting activity against plant fungi.We obtained mutants by the technology of low energy ion and screened out 6 mutant isolates which can effectively control postharvest anthracnose of apple fruits by plate test.From which,two strains(BS 80-6,BS100-6) showed significant control effect in vivo under room temperature and low temperature,and their control effects were 33.28%and 100% respectively in the fourteenth day.