Magnesium-ion conducting gel polymer electrolytes (GPE) were prepared and their electrochemical properties were characterized. The composition of GPE containing P(VdF-co-HFP), Mg(ClO4)(2)-EC/PC and SiO2 was optimized in consideration of ionic conductivity and mechanical stability. Solid state magnesium cell employing magnesium anode, GPE, and vanadium oxide cathode was assembled and its cycling characteristics were investigated. The Mg/GPE/V2O5 cell showed low initial discharge capacity of 58 mAh/g based on active V2O5 material and poor cycling characteristics. At present, the results show that the Mg/GPE/V2O5 cell has an inferior cycling performance in comparison with that of well-developed, lithium metal polymer cells. (C) 2004 Elsevier Ltd. All rights reserved.