<p>This study evaluated the thermal insulation characteristics of fresh food packaging boxes using a biodegradable polymer foam. Temperature is a critical factor in maintaining the freshness of perishable foods, and effective thermal insulation can enhance the efficiency of cold-chain distribution. Two forms of cornstarch insulation (grounded and foamed) were used to compare and analyze thermal conductivity. The experimental results showed that foamed cornstarch exhibited superior insulation performance, which can serve as foundational data for the development of environment-friendly packaging materials. In addition, the study assessed the thermal insulation performance of various packaging boxes, confirming that the biodegradable cornstarch box demonstrated a performance similar to that of styrofoam boxes. This study is expected to contribute to the development of sustainable packaging solutions.</p>