Composite material structures are widely used in fields such as aerospace, maritime vessels, transportation energy, etc. Due to assembly, functional layout, and maintenance reasons, some wall panel structures inevitably have big cutouts, which can easily lead to instability under load. Among them, there is currently a lack of relevant research on the local buckling instability of wall panels with big cutouts under tensile loading. This article conducts experimental study on the local buckling problem of carbon fiber reinforced composite laminates with big cutout under uniaxial tensile loading. For investigating the local buckling failure behavior around the cutout, the resistance strain gauge electrical measurement and DIC (Digital Image Correlation) optical measurement were mainly used to obtain the strain and the out of plane displacement around the cutout of composite laminates in the experiments, respectively. The experimental results indicate that the composite laminates with big cutout may experience local buckling instability at the edge of the opening hole before the overall structure fails due to strength failure, and the local buckling critical loads are influenced by the stacking sequences and the dimension of cutout.