The investigation focused on the adsorption of the blue methylene on banana peels powder. The studies led to determine contacting time (40 minutes for 90% elimination of substrate methylene blue). However, this contacting time can vary with dye concentration. The optimization of parameter such as the temperature, agitation and initial concentration of dye has showed a sensitive improvement of the capacity and rate adsorption. Moreover, the adsorption of this compound is well described by both Langmuir and Freundlich isotherm models.