In this study, new polyurethane composites have been prepared by the treatment and functionalized of waste leave sidr powder with polymeric methylene diphenylene diisocyanate (PMDI), and the mixing effect on the properties of these composites were evaluated using different weight percentages of carbon fibers (CFs). Thermal treatment of the prepared natural composites was done at different temperatures, where the studies used the XRD and SEM showed the heat treatment at 900 °C, lead to formation of Nanocomposites. On the other hand, the flammability test of these composites and hybrid composites (containing different % of CF) were a analysed using UL-94V methods, the results show, that these prepared composites were flammable and fire resistant. Also, the effect of CF on the ablation properties of these composites was evaluated using an oxygen-acetylene ablation device, and along with the increasing the content of CFs, the mass and linear ablation rates both decreases, while the insulations index were increased.