Abstract: According to hierarchical structural design idea, a high-performance polymethylallyl imide (PMI) foam was added between the unidirectional carbon fiber reinforced resin composite to prepare hierarchical composite honeycomb structure. The out-of-plane compressive performance of hierarchical composite honeycomb structures were studied, including the theoretical prediction and experimental verification of the out-of-plane compressive performance of hierarchical composite honeycomb structures. The relationship between the out-of-plane compressive properties of hierarchical composite honeycomb structure and the structural equivalent density was studied. The three-point bending performance of hierarchical composite honeycomb structure was studied, including theoretical prediction and experimental verification. The failure mode of the structure was predicted by theoretical research, the failure mode mechanism diagram was drawn, and the theoretical prediction results were verified by three-point bending test.