A novel core-shell ion-exchange resin composed of an ion-exchanging porous shell layer formed on a hard polymer core was prepared for application to HPLC. The effect of various core-shell ratios on the retention time and theoretical plate number (N) in the separation of carbohydrates was examined. A mixed aqueous sample of inositol, glucose, fructose and sucrose was reasonably separated under alkaline conditions (100 and 150 mmol/L NaOH) at flow rates of 0.4-1.0 mL/min. The retention time was linearly related to the thickness of the porous layer. The values of theoretical plate number(N) of glucose, fructose, and sucrose depend on the shell thickness at a flow rate of 0.5 mL/min when using the 100 and 150 mmol/L NaOH eluent.