Adsorption properties of cationic dye methylene blue (MB) onto poly (acrylic acid-co-acrylamide)/ attapulgite composite clay were investigated. The effects of various experimental parameters such as pH, concentration of the dye, temperature, contact time, adsorbent dosage, ionic strength and surfactant on adsorption process have been studied. Equilibrium isotherms for the adsorption of the dye were measured experimentally. Results were analyzed by Langmiur and Freundlich equation at different temperatures and the characteristic parameters for the adsorption isotherm were determined. The adsorption process has been found endothermic for MB in nature. The thermodynamic parameters such as Gibbs free energy, change in enthalpy and change in entropy have been calculated. The maximum adsorption capacity for MB was obtained as 1273.3 mg g-1 at the temperature of 60℃. It was observed that the kinetic data fitted well with a pseudo second-order equation. The results showed that the composite attapulgite clay could be employed as low-cost alternatives to traditional agent in wastewater treatment for the removal of color.