Based on the thermal physical parameters of shrimp, the equivalent heat capacity method was used to process latent heat in phase change, the finite difference method was proposed for modeling irregular shrimp, and the freezing times of symmetrical section in the shrimp freezing layer from the refrigerator bottom with 15 mm, 50 mm and 100 mm upwards were predicted, which were also validated by experiments. Compared numerical simulation results with experimental verification, it could be found that the correlation coefficient between simulated freezing time and test time curve was 0.996, the maximum error in the section center of shrimp was 1.85 K. It could be concluded that the numerical simulation could effectively predict the temperature distribution in the process of food freezing, which was of great significance for freezing processing, quality control and optimization of equipment of shrimp.