A novel cost-effective chicken feathers biochar (CFsBC) doped sulfonated polyethersulfone (SPES) proton exchange membrane was synthesized using solution casting and solvent evaporation method for microbial fuel cell application. The CFsBC was obtained through pyrolysis at different temperatures with an optimum yield at 550 °C with high nitrogen content (11.31%). Among the different bio-composite (BC) membranes prepared, a 10 wt% loading (BC-2) of CFsBC showed a better performance with a maximum tensile strength of 50 MPa, IEC of 1.15 meq g-1, and 28% water sorption. The highest proton conductivity of 0.093 S cm-1 with a power density of 0.115 Wm-2. The BC-2 membrane showed low oxygen diffusivity (6.8 × 10-8 m2s-1) and was well in agreement with that of estimation carried out through molecular dynamics simulation with an error of ±5%. The addition of CFsBC to SPES leads to a reduction of 46% friction-free volume due to its increased packing density that ultimately disrupts the oxygen diffusion path. The BC-2 membrane in MFC showed a removal efficiency (%) of 81 ± 0.25 for chemical oxygen demand in the wastewater. The economic assessment for the synthesized BC-2 showed a reduction in 30 times in cost as compared to Nafion 117 membrane. The low cost and high performance of BC membrane thereby showed huge potential for its applicability in MFC operation for wastewater treatment.