The electrochemical reduction of CO2 with a Cu electrode in CsOH/methanol-based electrolyte was investigated. The main products from CO2 were methane, ethylene, ethane. carbon monoxide and formic acid. A maximum Faradaic efficiency of ethylene was 32.3% at - 3.5 V vs. Ag/AgCl saturated KCl. The best methane formation efficiency was 8.3% at - 4.0 V. The ethylene/methane current efficiency ratio was in the range 2.9-7.9. In the CsOH/methanol, the efficiency of hydrogen formation, being a competitive reaction against CO2 reduction, was depressed to below 23%.