PURPOSE: To obtain a catalyst high in C2 selectivity and C2 yield and having a long durable life in the production of ethane.ethylene from methane by an oxidative coupling reaction.

CONSTITUTION: A mixed soln. of an alkali metal halide (e.g., lithium fluoride) and acetylacetonatosamrium or samarium acetate is heated to, be evaporated to dryness and the dried matter is baked and ground to obtain a catalyst (LiF-Sm2O3 catalyst). Methane is brought into contact with this catalyst to produce ethane and ethylene by an oxidative coupling reaction.