New generation biofuels are mainly produced from non-food crops or waste. While second generation ethanol is one of the main options, valeric esters can also be produced from lignocellulose through levulinic acid. However, only few experimental results are available to characterize their combustion behaviour. Using a traditional compression ignition engine converted to mono-cylinder operation, we have investigated the engine performances and emissions of butyl and pentyl valerate. This paper analyses the experimental results for blends of 20%vol of esters in gasoil, taking gasoil as the reference fuel. The butyl and pentyl valerate have a smaller cetane number and consequently the ignition delay of the blends are slightly longer. However, engine performances and emissions are not significantly modified by adding 20%vol of esters to gasoil. Butyl and Pentyl valerate then represent very good alternative biofuels for CI engines.