Abstract: The cylinder of offshore wind power bucket foundation is prone to buckling and instability when it is installed into the soil,which seriously affects the safety of the foundation structure. The thesis analyzes the stability of the bucket foundation in the sinking process and studies its instability mode and critical buckling load as well as the influence of the compartment and longitudinal stiffeners on the critical value of the internal and external pressure difference of the bucket. The results showed that the instability of the cylinder of the bucket foundation belongs to the extreme point instability and the nonlinear method should be used to determine the critical load of structural instability. Both the compartment and the stiffeners with appropriate spacing can increase the critical buckling load of the bucket. However,as the top of the tube top approaches the mud surface,its lifting effect gradually decreases,and the control condition of the internal and external pressure difference of the bucket is changed to prevent the soil in the bucket from permeating damage.