PURPOSE: To prepare 1,2-dichloroethane in high yield with suppressing the formation of ethylene dichloride as a by-product, by subjecting ethylene to oxychlorination using a catalyst having high performance comprising copper chloride, KCl and CsCl as cocatalysts.

CONSTITUTION: In preparing 1,2-dichloroethane by using a mixed gas of ethylene, hydrogen chloride and air or oxygen, a catalyst, comprising copper chloride as a main catalyst and potassium chloride and cesium chloride as cocatalysts in a weight ratio of CuCl2:KCl:CsCl of (1):(0.1W0.5):(0.1W0.5), is used. It is supported by a carrier having preferably a specific surface area of 100W350m2/g and ≥20vol% based on total pore volume of pores with pore diameters ≥100. This catalyst is especially useful in a fixed bed process.