The work aims to study the weakening effect of circular hole defects on lateral bearing capacity of honeycomb cardboard and corrugated cardboard. The finite element numerical calculation method was used based on ANSYS Workbench, and an eigenvalue buckling analysis was conducted on both types of cardboard. The tendency of critical buckling load of the two types cardboard with different hole sizes was analyzed, and the sensitivity of lateral bearing capacity to hole defects was explored. As the hole diameter increased, the buckling critical load of both honeycomb cardboard and corrugated cardboard gradually decreased. When the circular hole was greater than the critical value, the buckling load reduction rate of corrugated cardboard was significantly higher than that of honeycomb cardboard. As the hole diameter increases, the decrease rate of the lateral load-bearing capacity of honeycomb cardboard is slower than that of corrugated cardboard, and honeycomb cardboard exhibits a superior weakening effect of hole defects compared with corrugated cardboard.