This study investigates the effect of different pre-treatments on the bio-ethanol production from the soluble compounds of the organic fraction of the municipal solid wastes (OFMSW). The experimental evaluation was performed on leachate samples obtained after mixing OFMSW with water during 10 d. The most relevant result was that the acid and organosolv, using sulphuric acid as catalysts, pre-treatments yielded the best results. After the acid pre-treatment, the bio-ethanol production was 2.4 times higher than that obtained without pre-treatments. The main conclusion is that the pre-treatment significantly enhance the bio-ethanol production.