The textile industry is very important because its products are widely used by society, however, this activity has a great contribution to the contamination of water resources due to its effluents that contain large amounts of colorants, among which is the blue of methylene (MB) and methyl orange (MO), which can cause damage to the health of the living being, for this reason this study the removal of these dyes by adsorption using Eichhornia Crassipes (Water lily) with different treatments. The results show that the chemisorption removal process using two sites per dye molecule having an exothermic nature for the water-treated lily and for the NaOH-treated lily is endothermic. The maximum adsorption capacity of 228.9 mg/g for MB (60 °C) and 155.38 mg/g (30 °C) for MO with the NaOH treatment. The SEM analysis shows that there are significant changes in the surface due to the treatments. The XRD patterns indicate that with the pretreatment with NaOH the crystallinity of WL increases while the treatment with water maintains the presence of amorphous cellulose. In the FTIR spectra, bands corresponding to different functional groups such as lignin, cellulose and hemicellulose that participate in the adsorption of both dyes are observed.