In spite of composite materials having lots of advantages from the mechanical performance point of view, these days due to stringent fire regulations, flammability has often become the primary issue of consideration. A number of chemical additives are used for preparing polymer composites requiring improved flammability performance, but in most cases, the addition of such a flame retardant adversely affects the mechanical properties. Furthermore, it has been shown that the chemical toxicity not only has a lasting effect on human life, but may cause fatal damages during a fire situation. As a consequence, the recent developments of flame retardant (FR) materials have focused on finding natural materials that can replace the chemical compounds. Among these materials for FR synthesis, protein has attracted great attention due to its abundance, self-extinguishing properties and good compatibility with polymer matrices. Yet, its insufficient flame retardancy in raw form and poor processability still pose challenges. In this context, we have used chemically treated chicken feather fibre as a FR additive for polypropylene (PP). Owing to considerably changed physical properties after the treatment the FR additive not only overcame the inherent limitations of the protein but also achieved uniform dispersion during melt compounding with PP. It has also been shown that the particle size and its distribution can be significantly affected by the chemical treatment used in this process. The modified composites successfully achieved the highest fire performance grade, V0, in the UL-94 test along with significantly improved mechanical properties compared to those of conventional ammonium polyphosphate/PP composites. Furthermore, the paper will also explore the possibility of commercializing the intellectual property generated by this research, including price reduction and the advantage generated by converting a landfill material to a value-added product.