The adsorption methods have been extensively used by various researchers for the removal of dyes from industrial waste water. In the current work, the leaves of Thorn apple [Datura staramonium] treated with sulphuric acid and formaldehyde were used as an adsorbent for the elimination of congo red and magenta from an industrial waste water. The adsorption characteristics of these two dyes on activated Thorn apple leaf powder (TALP) were evaluated as a function of pH, adsorbent dose, initial concentration of adsorbate, temperature. The efficient adsorption was established to be in pH range 3.8 to 7.4, adsorbent dose 0.5 g to 0.8 g, initial concentration (1 x 10-5 to 5 x 10-5 M) and Temperature range (308 to 318 K). The results tell that ceiling adsorption of two dyes onto TALP is in the range of 63.8% to 89.7%. The adsorption data fixed well into Freundlich and Langmuir adsorption models. The results show that Thorn apple leaf powder holds a great prospective in removal of congo-red and magenta dyes from industrial wastewater.