The presence of high concentration of As(III) (arsenite) and As(V) (arsenate) in water system creates severe health problems to the human being and other aquatic animals. In this research, a novel Fe3O4/CSAC adsorbent was prepared by the thermal method using cigarette soot activated carbon (CSAC) as a template. Different instrumental techniques like XRD, SEM, EDX, TEM, VSM, BET, Zeta potential and FTIR study were used to confirm the formation of Fe3O4/CSAC. This material showed high surface area (575.604m2/g), low pore size (6.8nm), small particle size (less than 10nm) and good magnetic properties (10.77emu/g), which made the material highly effective for arsenic removal. The adsorption of arsenic was highly pH dependent and 91% and 93% of As(III) and As(V) were removed by this adsorbent at pH7 and 3. The adsorption process followed the Langmuir isotherm model with the uptake capacities of 80.99 and 107.96mg/g for As(III) and As(V), respectively. The adsorption data were best fitted to the pseudo second order kinetics model with the rapid adsorption in just 90min. In presence of Cl−, NO3−, SO42−, CO32– and PO43− anions also, the Fe3O4/CSAC showed the significant removal of As(III) and As(V). About 89% and 91% of As(III) and As(V) were desorbed with 0.5M NaOH solution from Fe3O4/CSAC surface and the regenerated adsorbent can be used up to four consecutive cycles without any major decrease in removal efficiency. The hydroxyl groups on the Fe3O4/CSAC played a key role for the adsorption of As(III) and As(V). The Fe3O4/CSAC was found to be a good novel adsorbent for arsenic removal from the water system.