For the first time, the oscillatory behavior during CO oxidation over Ni foil has been discovered under atmospheric pressure conditions in the temperature range of 570-630 A degrees C. The oscillatory behavior occurred in CO excess in contrast to the well-known oscillations during CO oxidation over Pt, Pd, Ir, and Ru. The periodic variation of oxygen imbalance together with the variation of color changes during the oscillations indicated that the oscillations were closely connected with the reversible oxidation of Ni to NiO. The observation of oscillations in a pulse supply mode proved their kinetic origin. The oscillations were accompanied by the propagation of the oxidation and reduction fronts which could be observed with the naked eye. Temporal and spatial self-organization during CO oxidation over Ni foil. [GRAPHICS] .