The aim of this study was the evaluation of the physicochemical characteristics of surface modified Dijah-Monkin bentonite clay. The clay was modified by calcination and treatment with hydrochloric acid. The natural and modified clays were characterized by x-ray fluorescence (XRF), Fourier transform infrared (FTIR), x-ray diffraction (XRD), electron dispersive x-ray (EDX), thermogravimetric analysis (TG), scanning electron microscopy (SEM), elemental composition, cation exchange capacity (CEC), Brunauer-Emmett-Teller (BET) specific surface area and methylene blue adsorption. The XRF displayed the presence of SiO2 and Al2O3 in the range of 61.6-65.6wt% and 19.4-21.7wt%, respectively. The FTIR spectra showed the existence of Al-OH, Al-O, Si-O, and Si-O-Si functional groups in all clay samples, confirming the presence of hydrated aluminosilicate in the clay. The BET surface area decreased from 23.5 to 17.1m(2)/g after acid treatment, while the CEC of clay samples range between 40.7 and 20.2 mEq/100g. The minerals present in clays are montmorillonite, quartz, kaolinite, and muscouvite. The maximum methylene blue adsorption were estimated as 59, 48, and 45.8mg/g for natural, calcined, and acidified bentonite, respectively. The structural formula for one-layer unit of montmorillonite was determined as K0.722Ca0.155[Si-7.686](iv)[Al3.054Ti0.11]O-vi(20)(OH)(4). The natural Dijah-Monkin bentonite is a promising adsorbent candidate for the removal of charged pollutants.