In this study, activated carbon that prepared from unused wood of citrus shrub by chemical activation method using phosphoric acid as activating agent was characterized by SEM and FTIR method. The chemically modified adsorbent was identified by observing developed active functional group and porosity on surface of resultant carbon. These qualities are essential for effective adsorption of adsorbate and removal of pollutants from aqueous solution. In this study SEM images indicated developed micro and mesopores while FTIR graphs were represented formation of active phosphorous and oxygen containing functional groups such as P-O-P, P- O-C and P=OOH etc. On surface of AC. Based on these results the resultant carbon is promising adsorbent for removal of polar and non-polar pollutants from aqueous solution.