Pickled food may contain spore pathogenic bacteria and spoilage bacteria， high pressure thermal sterilization (HPTS) can kill these spores， and sodium chloride in pickled food may improve its bactericidal effect. The bactericidal effect of high pressure thermal sterilization (600 MPa， 75 ℃) combined with sodium chloride (15%， 25%， saturated sodium chloride solution) on Bacillus subtilis spores was studied. After treatment， the leakage rate of 2， 6-dipyridinolinic acid (DPA) and the damage of the intima of the spores were measured. The changes of spore intima， protein secondary structure and nucleic acid stability were analyzed by Fourier transform infrared spectroscopy (FTIR). The results showed that the combined treatment of 600 MPa， 75 ℃ and 15% sodium chloride had the best inactivation effect on Bacillus subtilis spore [5.43 lg (CFU/mL)]， and the DPA leakage rate of spore under this condition was 92%. HPTS combined with 15% sodium chloride had the greatest damage to the intima， protein secondary structure and nucleic acid stability. Under the conditions of 600 MPa， 75 ℃ binding concentration of 25% and saturated sodium chloride， the kill amount of treated spores was about [3.48 lg (CFU/mL)] and [3.08 lg (CFU/mL)]， and the leakage rate of DPA was 82% and 63%， respectively. Compared with 15% sodium chloride， the inner membrane permeability of the spore was reduced， the α-helix ratio of the secondary structure of the spore protein increased significantly， and the secondary structure of the protein was more orderly. Studies have shown that 25% and saturated sodium chloride unexpectedly protected Bacillus subtilis spores and reduced the damage of the spore intima， proteins and nucleic acids caused by HPTS treatment.