Process for the manufacture of 1,2-dichloroethane (DCE) starting with a hydrocarbon source which is subjected to a cracking thus producing a mixture of cracking products then subjected to treatment steps to obtain a mixture of products containing ethylene. The mixture is afterwards subjected to a first separation step into a fraction enriched with the compounds that are lighter than ethylene containing some of the ethylene conveyed to a chlorination reactor in which most of the ethylene is converted to DCE, and into a fraction F1 which is subjected to a second separation step into a fraction F2 and into a heavy fraction. Fraction F2 is afterwards subjected to a third separation step into a fraction enriched with ethylene conveyed to an oxychlorination reactor in which most of the ethylene is converted to DCE, and into a fraction F3 mainly composed of ethane.