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Because of the increasingly environmental and health concerns over conventional polyurethanes that manifested by toxic isocyanates and unsustainable fossil-based polyols, there is a great interest in non-isocyanate polyurethanes (NIPUs) production from renewable biomass resources. Herein, under the concept of biorefinery, the sweet potato residue (SPR) from starch industry, rich in non-biological toxicity starch, holocellulose and vegetable protein, was considered as the raw material for the NIPUs. During the process, the crude SPR was first liquified into chain-extending homogeneous molecules that were enriched in active hydroxyl-groups, followed by undergoing epoxidation and carbonation. Then, the obtained cyclic carbonate precursor was crosslinked with amines for the final NIPUs. The as-prepared SPR-derived NIPUs exhibited attractive mechanical and thermodynamic properties. To test the applicability, the food preservation performances of the SPR-derived NIPUs was further investigated. After spray coating the NIPUs on the banana peel, the dark brown spots in the testing group were significantly reduced after half-month storage. Therefore, the SPR-derived NIPUs provides a foundation for the futural food packaging alternatives. [Display omitted] • Non-isocyanate polyurethane films were prepared using sweet potato residues. • The sweet potato residue was functionalized before crosslinking with amines. • The non-isocyanate polyurethane films exhibited good mechanical properties. • The non-isocyanate polyurethanes performances were dependent on the type of amines. • The non-isocyanate polyurethane films can be used for foods preservation. [ABSTRACT FROM AUTHOR]