The catalytic ignition-extinction limits and oscillatory behavior of the CO oxidn. at atm. pressure over Pd supported on glass fibers were investigated as a function of catalyst sp. surface area, surface concn. and dispersion of Pd. The ignition-extinction limits for each specific catalyst depend on the CO concn. and the gas flow rate. Three reactivity regions were found as a function of temp. and CO concn.: high reactivity region with conversion close to 100%, low reactivity region and the region of multiplicity of steady states. In the region of multiplicity the self-sustained oscillations with a period up to 6 h were obsd. for the catalyst with Pd loading of 0.2%wt. High and low reactivity states of the catalyst were assocd. with reduced and oxidized state of Pd on the glass fiber surface. It is believed that the reaction rate oscillations are due to the cycles of Pd partial oxidn.-redn. [on SciFinder (R)]