The electrochemical fluorination of trichloroethylene in anhydrous hydrogen fluoride at 0°C and at constant cell po tential was investigated. A microprocessor-aided electrochemical fluorination reactor system that yields highly reproduci ble results was utilized. The following major two-carbon-chain products were observed: CHC12-CC12F, CHC12-CC1F2, CHC1F-CC12F, and CC12F-CC1F2. The first step in the reaction sequence was determined to be fluorine addition to the double bond, followed by replacement of first hydrogen and then chlorine by fluorine. Polymerization reactions yielded higher molecu lar weight or possibly ring-type chlorofluorohydrocarbons. A comparison of the reaction products of electrochemical and chemical fluorinations of trichloroethylene is also discussed.