Polyurethanes (PUs) are polymers obtained by reacting diisocyanates with a group of polyols. The first synthesized PU compounds were prepared using petroleum subproduct compounds. In this research study, biomass-containing polyols, which have been studied by other scientists, were prepared using potato crust and polymerized with diisocyanates to produce PU foam. Polyol reactions were carried out using the microwave heating method. Synthesis reactions and structural properties of polyols have been studied in many aspects. The most available polyol was used for PU synthesis. Different formulations were tried for PU synthesis and as a result, PU foam containing nearly 25% starch-polyol was synthesized. The chemical structure of PU polymer was identified by ATR-FTIR spectroscopy and crystallographic properties by WA-XRD analysis. The physical and mechanical properties of PU foam, which is used as a large number of building and construction materials, including thermal insulation materials, were evaluated by comparing them with a commercial PU foam.According to the results of our research, it was detected that the incorporation of biomass into the structure of PU polymer improved its density, heat conduction coefficient, pressure based mechanical properties. PU foam derived from potato waste has a WA XRD-ray diffraction peak between 13.1-28.5o. This data is between 12.5-23o in synthetic commercial foam and has been positively improved in the product we synthesized as a result of combining biomass into the structure. The synthesized biomass-based PU foam can be used as thermal insulation material. Biomass-based PU foam has been synthesized with features that can be used as a thermal insulation material.