Abstract: Base on the research of the generation and migration of fission product in the primary loop, the calculation model for the fission product in the primary loop is established, and the calculation code CPFP2.0 with a good man-machine interface is developed. The code CPFP2.0 is tested by the similar codes in other countries and the engineering data from EPR nuclear power plants. The test results show that tolerance scope between CPFP2.0 and the similar codes in other countries is within the acceptable range of engineering practice for tested case, and the difference between calculation result of CPFP2.0 and the engineering data of EPR nuclear power plant is negligible.