We have investigated the current creation accompanied by the water decomposition H 2 O → OH + H caused by various catalytically active electrodes with different electrochemical potentials, both without external electric voltage on these electrodes and with the applied voltage V 0 = ±9.7 V. It is found that the current value and its time dependence are essentially influenced by such factors as thermal and natural (in ambient atmosphere) oxidation of electrodes (made of Al, Si, Yb, Ni, Ti, Cr 3 Si, and Ni 3 Si), changing their relief (texturing, polishing), and the electrolytic deposition of palladium as an impurity on the surface (Ti, Cr 3 Si). Changes in the current caused by the above factors are realized as a consequence of changes in both the electron work function inherent to these electrodes and their catalytical activity concerning the water decomposition both in the absence and the presence of the external voltage V 0 .