Abstract: This research further develops and improves the test method of blade component size,experimental and numerical researches have been carried out on the composite web component specimens under compressive loads,and reveal the buckling failure mechanism of the web structure sample from the inside. The research reveals that the composite web specimen has typical buckling characteristics. In the post-buckling stage,the large local deformation of the specimen caused by the yield and crushing of the core material is the main reason that the specimen loses its principal load-bearing capacity. The underlying source of nonlinear structural response and buckling instability of the specimen is the initial flaws created by variables such as uneven material distribution during the production process.