In this study the efficiency of crystal violet dye removal from aqueous solutions using lilac tree leaf powder as adsorbent material was tested. After adsorbent surface analysis by SEM and FTIR technics, the influence of six controllable factor on dye adsorption process was assesses using a L27 Taguchi experimental design. The optimum adsorption conditions and the controllable factors significance were established by evaluation of signal-to-noise ratio (S/N). ANOVA analysis revealed the percentage contribution of each factor in crystal violet removal. Langmuir isotherm and pseudo-second order kinetic model characterized the process and the maximum adsorption capacity was higher than other similar adsorbents previously used in literature. The thermodynamic parameters reveal a favorable, spontaneous and endothermic adsorption based on physisorption mechanism.