The chitosan-coated neem flower powder was prepared and employed as an adsorbent for the removal of cationic methylene blue from an aqueous medium. The interaction of chitosan with neem flower was concluded by FTIR. The BET surface area was evaluated for the prepared NFC adsorbent. The adsorption of methylene blue dye onto chitosan-coated neem flower powder (bio-adsorbent) was carried out by varying the concentration of dye, pH, temperature and concentration of adsorbent. The adsorption capacity was evaluated by using Freundlich and Langmuir models. The adsorption data were further analysed with the help of pseudo-first and second-order kinetic models. The thermodynamic parameters were evaluated to comprehend the nature of the adsorption process.