The study is devoted to the effect of preparation on the performance of CsX zeolite as basic catalyst for the oxidative methylation of toluene with methane. The conversion, C-8-selectivity and C-8-yield are significantly higher over the impregnated zeolite than those over the ion exchanged one. Intermediate position, but closer to the impregnated zeolite holds the solid-phase ion-exchanged zeolite. The structural characterization, realized by X-ray powder diffraction and IR lattice vibrations, indicates that the zeolite crystal structure is well stabilized and is mainly not influenced by the mode of preparation. Non-framework species (evolved from CsCl) are best presented in the structure of the impregnated zeolite, which is also the most active and selective catalyst of the three catalysts studied. The catalytic behaviour of all catalysts is not directly related to the overall basicity.