The interaction of acetylene with surface sites of SiO₂, TiO₂, CaO, MgO, Al₂O₃, Ga₂O₃, La₂O₃, and ZrO₂ oxides was studied. Two main types of acetylene adsorption complexes were found: first, complexes formed by weak reversible adsorption at O²⁻ sites and basic OH groups and, second, stable complexes formed by the dissociative adsorption of acetylene at Me^δ+–O^δ− pairs with the formation of acetylide species. The position of the C–H band in weakly adsorbed complexes and CC bands in strongly adsorbed complexes can be used for the sensitive characterization of oxide basicity. The measurements performed at elevated acetylene pressures (10–20 Torr) give information on the total basicity of oxides, whereas the analysis of the complexes formed at low pressures (∼0.2 Torr) characterizes the properties of specific absorption sites. The interaction of acetylene with surface sites was mainly reversible; however, the products of acetylene oligomerization could be observed in the long-term experiments.