AbstractThe role of ubiquinone in the Golgi apparatus is still unknown, even if it might be considered as a lipid marker of the Golgi compartment because of its high content in these subcellular fractions.In vivomodulation of ubiquinone with ethanol andin vitropentane extraction show that ubiquinone is not required either for NADH‐ferricyanide reductase, acetaldehyde dehydrogenase activity, or Ca2+and Mg2+stimulated ATPases.Since ubiquinone does not seem to be involved in these enzymic activities in Golgi compartments, other possible functions are discussed, related to a role in membrane fluidity or as a barrier to the propagation of free radical