Hard coatings with high damping capacity are of great value for vibration reduction and improvement of fatigue life of thin-walled structures such as blades. At present, there is an urgent need for a reasonable analysis method to calculate the fatigue life of hard coating damping structures and to analyze it′s the influence of the hard coating on structural life. In this study, the random vibration fatigue life of cantilever thin-walled beam with hard coating is calculated by finite element method. Firstly, taking a cantilever thin-walled beam as the object, the modal harmonic response of the structure, before and after the hard coating was attached on it, was calculated, and the modal frequency and stress response function in the dangerous area were obtained respectively. Then, the random vibration fatigue life of hard coating cantilever beam is calculated by using the frequency domain analysis method, and the corresponding fatigue life and damage nephogram are obtained. Finally, the fatigue life and damage behavior of the structure, before and after coated, were obtained by exerting the random vibration foundation excitation on the electromagnetic vibration table. The results show that hard coatings can prolong the vibration fatigue life of cantilever beam and slow down the rate of fatigue crack growth. By comparing the error analysis of simulation and test results, the rationality of the method of simulating the vibration fatigue life of the structure is verified.