Optimum electrocrystallisation conditions of PbO2 have been investigated in acetonitrile by controlling experimental parameters such as water content, current density, electrolyte concentration, and acidity. It was determined that the crystallinity, conductivity and beta-content of PbO2 films are highly dependent on these factors and that electrodeposition solution, which has 6 M water, 0.1 M lead perchlorate and no acid, gave the best crystalline PbO2 with 99% of beta form. The conductivity value of this film was 6028 S/cm. All analyses were confirmed by XRD method. (C) 2000 Elsevier Science B.V. All rights reserved.