Ion exchange performance to remove ammonia-nitrogen in water was studied using commercially available sodium base cation exchange resin in the batch and continuous column reactors. Cation exchange resin used in this study was more effective than activated carbon or zeolite for ammonia-nitrogen removal. With large resin amount or low initial concentration, ammonia-nitrogen removal characteristics was increased. On considering the relation between the breakthrough capacity and ammonia-nitrogen concentration of the influent, the use of cation exchange resin were suitable for the higher order water treatment. The commercially available strong base cation exchange resin used in this study could be effectively used as economic material for treatment of the groundwater.