Abstract: To investigate the subsiding of honeycomb sandwich panel or beam , a theoretic model of a circular cellhoneycomb subjected to axial loading is developed. The formulas of the critical press st ress on the skin are derived ,a perfect design theory of honeycomb sandwich panel or beam is established , and a novel method of iterative optimization design is presented. Finally , the result with a numeric simulation method verifies that the theoretic model inthis paper is accurate and efficient . The study will provide an important theoretical basis for advanced improvementof the honeycomb sandwich plate or beam.