In order to satisfy the technics and maintenance requirements for the structure of the composite web,holes are ineluctable on the web of spar and difform holes have different carrying capacity. By studying difform holes on the web with buckling test under the shear load , different buckling load and failure mode of structure are established. Finite element analysis was used to analyze the buckling behavior of the web, and the analysis results are accordable with experimental results. Experiment results also reveal that the composite web can bear greater load after buckling.