"Mathematical model was developed to determine reliable design conditions of electrodialysis (ED) system with a monopolar ion-exchange membrane and assess its performance. Good agreement was obtained between the simulated results of the mathematical model and the measured data. Removal of nitrogenous ions of NH[GRAPHICS]-N was easier than that of PO[GRAPHICS]-P ions because of high mobility due to the small molecular weight. The supplied voltage (E) and the concentration ratio of concentrate to dilute (k) were important controlling factors for the removal rate of nutrient salts (S-i). From the experimental and simulated results, it is believed that the developed model is applicable to the flow analysis of ED system."