Water is essential for all living things however its pain has become serious. Many industrial activities cause its pollution by the release of polluting byproduct. Waste water treatment is hence necessary. In this context, the waste water of the textile industry containing Red Acid 52 was treated by the solid waste of the washed natural phosphate byproduct. Natural phosphate was also studied. The solid materials were first characterized by chemical analysis, Fourier Transform Infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The phosphate materials were after that, tested in the adsorption of the Red Acid 52. The experimental data indicated that the phosphate waste rock allowed the removal of Red Acid 52. Its maximum retention capacity attained 18.4 mg.g-1. Calcinations of materials inhibits the removal capacity found reduced by 60 to 70%. The adsorption kinetics of the Red Acid 52 on the material is well described by the pseudo second order model while the adsorption isotherms are identified by the Langmuir model. Hereafter, the thermodynamic study revealed that the adsorption process is spontaneous and exothermic. Keywords: Waste water, Phosphate co-product, Adsorption, Red Acid 52.