Awater-swollen type of poly(vinyl alcohol) (PVA)/poly(styrene sulfonic acid-co-maleic acid) (PSSA-MA) cation-exchange membrane was prepared and characterized in terms of its electrochemical properties including ion-exchange capacity (IEC), electrical resistance, and transport number, etc. PVA/PSSA-MA membranes exhibited low electrical resistance and highly swel領(lǐng) property. In spite of 24 times higher water swel領(lǐng) ratio (WSR) than that of CMX (Tokuyama Corp., Japan), the transport number of the prepared membrane was comparable to that of the commercial membrane (tn > 0.93). Moreover, the electric resistance of PVA/PSSA-MA membrane was measured as low as 1.01.5cm2. Further, in this study, interrelation between the membrane characteristics and crosslinking was investigated, and the result exhibited that the crosslinking degree is one of major factors affecting the ion transport through a water-swollen ion-exchange membrane (IEM). ? 2002 Elsevier Science B.V. All rights reserved.