Proton exchange membranes were synthesized from the Polyvinyl Alcohol copolymer (PVA) crosslinked with potassium hydroxide (KOH) and formaldehyde (CH2O), and loaded with vanadium pentoxide in amounts of 0.5%, 1.0% and 1.5% to evaluate their application in fuel cells. The physicochemical and mechanical properties of the membranes were characterized. The results show that the membrane loaded at 1.5% presented the highest ion exchange capacity (1.1 meq/g) and a very good water retention, due to the optimum level of load achieved, allowing a correct interaction between the Va2O5 and the polymer matrix, while the 0.5% loaded one showed better mechanical properties (maximum stress of 35.9 MPa, maximum deformation of 218.9%, Young's modulus of 135.4 MPa) and the FTIR tests confirmed the presence of Va2O5 in the polymer. These results demonstrate adequate characteristics of the prepared membranes to be used in fuel cells.