Surface-functionalizations are of essential importance for diverse areas from biomedicine to biosensing, nanocomposites, water treatment, and energy harvesting devices. One facile and rapid way to functionalize any materials surface is by mussel inspired polydopamine (PDA) coating. It has been realized that dopamine (DA), the precursor, can be coated virtually on any substrates in presence of a buffer of pH ~ 8.5. Over the past 20 years, an overwhelming interest has been noticed around cellulose based materials specially nanofibers (CNFs) shown due to its many unique characteristics including high stiffness and modulus, great transparency well biodegradability, biocompatibility and low production cost. Despite of the facts, pristine cellulose often suffers from certain characteristic limitations in biomaterial applications due to the lack of appropriate surface functionalities. This research therefore aims to develop cellulose based composite materials suitable for biomedical applications, precisely electrode material for biosensors. The electrodes were made of controlled amount of polydopamine treated cellulose nanofiber composite. When investigated the mechanical properties of the composites, significant improvement was observed. Moreover, the composites exhibited good sensing behaviors under electrochemical investigations, leading them to be a promising material for biosensing applications.