Addressing plastic pollution and reducing reliance on petroleum reserves necessitates the development of bio-based materials from renewable resources. Lignin-carbohydrate complexes (LCC) extracted from lignocellulose, abundant in aromatic rings and hydroxyl groups, offer a promising alternative to conventional polyols in polyurethane synthesis. Historically, the limited solubility of LCC in polyols has posed significant challenges in fabricating high-performance biomass-based polyurethanes. This study presents an innovative LCC-based polyurethane elastomer, synthesized from LCC, polyols, and isocyanate building blocks. By replacing traditional polyols with hydroxyl-rich LCC, the resulting polyurethane elastomer (PUC) exhibits exceptional mechanical properties and photothermal conversion efficiency. The material boasts a maximum tensile strength of 20.94 MPa, a fracture strain of 1167.39 %, an elastic recovery rate of 91.4 %, and a peak photothermal conversion temperature of 125 °C. These outstanding attributes are ascribed to a robust network of dynamic covalent and hydrogen bonds. Moreover, the incorporation of LCC notably enhances the recyclability of the polyurethane elastomer and provides effective UV-blocking properties. This research not only broadens the spectrum of raw materials available for polyurethane production but also introduces innovative methodologies for the practical utilization of LCC, representing a notable advancement in sustainable materials science.