In order to conduct the analysis of the mode and node fatigue life of the modified jacket platform to evaluate its reliability, based on SACS software combined with the S-N curve method and Airy wave theory, a three-dimensional finite element model is established for the fatigue analysis of the LD22-1 CEP jacket platform renovation project. The fatigue life of the jacket platform is calculated and analyzed by the numerical model. The calculation results show that the fatigue lives of nodes X107, X106 and X406 are 24.49, 34.82 and 40.38 years, respectively, which are less than the design fatigue life; except that the three nodes do not meet the design requirements of the fatigue life, the other nodes meet the design requirements of the fatigue life. To ensure the safe operation of the platform, it is necessary to strengthen the design of the above three nodes and strengthen the monitoring of the fatigue nodes during operation.