As an important connecting and fastening part of wind turbine blade,blade root bolt plays an important role in the operation of wind turbine. In this paper,the connecting bolt between blade and pitch bearing of 2 MW wind turbine is taken as the research object,and a dynamic strength analysis model of blade root bolt of wind turbine is established under the conditions of three-dimensional turbulent aerodynamic load,gravity load and centrifugal force load. Under the condition of normal operation and partial bolt fracture failure,the stress distribution of blade root connecting bolt is obtained by finite element analysis.Compared with the traditional bolt strength analysis,this paper can get a more real trend of bolt stress change,the maximum stress value and its location. In order to provide theoretical basis for more accurate monitoring of some key points of blade root,it is of great significance to ensure the normal operation of wind turbine.