Abstract: In a method for producing 1,2-dichloroethane by an oxychlorination reaction of ethylene, hydrogen chloride and oxygen, a continuous method for producing 1,2-dichloroethane, which comprises cooling a gas discharged from an oxychlorination reactor to condense and separate 1,2-dichloroethane and water therefrom, further removing hydrogen chloride and carbon dioxide therefrom, then mixing oxygen and nitrogen thereto so that the oxygen concentration becomes from 20 to 30 vol % and the ethylene concentration becomes from 1 to 3 vol % and supplying the gas mixture thus adjusted to an oxychlorination reactor.