The effect of Pt-Cu/C catalyst composition on the activity and selectivity in the reaction of 1,2-dichloroethane dechlorination in a H-2-containing atmosphere has been investigated. For monometallic Pt catalysts and those with Cu/Pt atomic ratio less than or equal to 1, the reaction products are almost entirely ethane and monochloroethane. However, increasing the Cu/Pt ratio increases the selectivity towards ethylene. Approximately 90% selectivity towards ethylene is obtained for catalysts with Cu/Pt ratio greater than or equal to 9. Monometallic Cu/C produce only ethylene, but the activity is two orders of magnitude lower than that of other catalysts studied. With time on stream during the initial 2-30 h there is a continuous increase in selectivity towards ethylene at the expense of ethane. This behavior was rationalized in terms of equilibration of bimetallic particle surface composition exposed to the reaction mixture.