The invention provides a foaming material prepared from modified corn straw. The foaming material prepared from the modified corn straw can be naturally degraded. The problem of flammability of the foaming material produced from the corn straw at present is solved by esterification grafting modification of the corn straw, and the foaming material has good compression resistance and high rebound rate. The modified corn straw foaming material has good comprehensive application performance, can be popularized and applied in buffering, shock-proof, fire-proof and heat-insulating packaging materials, and has practical significance for comprehensive utilization of agricultural waste straw.