The synthesis of polycrystalline thin films of cubic ZnSe by electrochemical plating on conducting substrates is described. The influence of deposition parameters such as electrolyte composition, deposition potential and temperature on the crystallinity and on the chemical composition of the films is discussed. Of the various plating techniques (potentiostatic, potentiodynamic pulse and galvanostatic), potentiostatic plating offers the best control of film composition. An excess of Se with respect to perfect stoichiometry cannot be avoided by adjusting electrolyte composition and deposition potential, but can be decreased by vacuum annealing.