This study investigates the efficiency of human hair as a low-cost, sustainable adsorbent for removing methylene blue (MB), a common cationic dye, from aqueous solutions simulating industrial effluents. Through various experiments involving different hair masses, agitation, solution concentrations, and contact times, the adsorption process was optimized and evaluated using spectrophotometry and isotherm models. The model that best describes the adsorption by hair is the Freundlich model confirming high adsorption efficiencies, reaching up to 97%, demonstrating human hair's potential in wastewater treatment applications. We believe that bioadsorption of methylene blue using human hair is an excellent solution to an environmental problem, as it is low-cost and uses a waste material.