At present,most of the structural crack propagation path judgment in helicopters is based on experience,lack of theoretical numerical simulation and effective analysis methods.The paper based on abaqus finite element software and practical experience seting up initial crack, a typical helicopter structure was selected for crack propagation simulation,investigating corrosion area and strengthening slot on crack propagation. The method and conclusion presented in this paper provide a new idea for the crack propagation path and damage tolerance design of helicopter structure, and provide some references for the improvement of engineering desing..