To provide a method for purifying 1,2-dichloroethane by distilling and purifying various crude 1,2-dichloroethane (EDC) products having different purities, respectively, in a process for producing vinyl chloride monomer(VCM), capable of largely reducing the consumption of steam to profitably produce the EDC.

This method for purifying 1,2-dichlorethane comprises distilling a plurality of crude EDC products having different highly boiling point impurity concentrations to separate a distillate having a low impurity concentration from a bottom product having an increased impurity concentration. Therein, a distillation device comprising two distillation towers is used. In the distillation device, the first distillation tower is operated at a higher pressure than that of the second distillation tower, and the overhead distillate of the first distillation tower is used as a heat source for the reboiler of the second distillation tower. The high boiling point impurity concentrations of the crude EDC products fed into the towers are different from each other, and at least two kinds of the crude EDC products having different high boiling point impurity concentrations are preferably fed into the different places of the towers in response to the high boiling point impurity concentrations.