This paper aims to investigate the adsorption process of a new composite adsorbent prepared from chitosan (Ch) and dolomite (Do) for removal of lead ions from aqueous solutions. The adsorption process of Pb(2+)ions onto Ch-Do composite adsorbent as initial Pb(2+)concentration, solution pH, temperature, contact time and desorption was investigated. From the results, it has been observed that the highest removal efficiency is approximately 89% at contact time of 6 h, initial Pb(2+)concentration of 500 mg L-1, adsorbent dosage of 100 mg and agitation speed of 150 rpm at pH 4.0. Langmuir isotherm has a better fit with the experimental isotherm data (R-2 = 0.920). The maximum Pb(2+)adsorption capacity from the Langmuir model was found as 0.332 mol kg(-1)at 25 degrees C Also, it performs pseudo-second-order superior performance in kinetic behaviour compared to other used kinetic models (R-2 = 0.904). Thermodynamic parameters showed the Pb(2+)adsorption onto Ch-Do was endothermic, spontaneous and possible. The desorption studies have shown that Ch-Do composite adsorbent has a good adsorption/desorption performance for Pb(2+)ions.