Abstract An experimental investigation of the ignition of methaneacetyleneoxygenargon mixtures was carried out behind reflected shock waves over the temperature range 1400–1900 K and reaction pressures between 1 and 4 bar. Pure methane, acetylene, and methaneacetylene mixtures ( C 2H 2 CH 4 = 0.1–1 ) were used in the investigation. The observed ignition delay of acetylenemethane mixtures lie between those of pure methane and acetylene. A 53-step reaction mechanism for the combined oxidation of methaneacetylene mixture was numerically integrated to yield the rate of change with time of the species concentration, temperature, and pressure. The computed ignition delays compare very well with the experimental results, and since the ignition delays for methaneacetylene mixtures lie between those of pure methane and acetylene, it is suggested that a chemical coupling exists between the two oxidation systems.