For bolts on the pitch bearing of the connection between the blade and the hub of the 1. 5 MW wind turbine unit,a method to calculate the fatigue damage value of connecting bolts was proposed. First,a reasonable finite element model was established by ABAQUS and moment load to the center of the blade root was added. Then the bending moment time history spectrum was transformed into the stress time history spectrum by MATLAB. And the stress time history spectrum was processed by the rain flow counting method. Finally,the fatigue analysis of the bolt was calculated by the Miner linear cumulative damage theory and S-N curve. The results showed that the fatigue damage value of the bolt was within the safety range,and the fatigue damage of the bolt before the wind turbine reached the service life was very small. The research work can guide the optimal design of the connecting bolts on the entire wind turbine generator and provide reference for fatigue design and life analysis of bolts.