Partial oxidation process of liquid fuels, selected from hydrocarbon and/or oxygenated compounds, together with gaseous fuels, selected from hydrocarbon compounds, natural gas and LPG, by means of a suitable catalytic system comprising the following steps: premixing the reagents and possibly heating them to temperatures ranging from 25 to 400.degree. C., said reagents consisting of said liquid fuels, said gaseous fuels and oxygen or air or oxygen enriched air, optionally in the presence of vapor and/or CO.sub.2; reacting the mixture of reagents in the catalytic zone, at inlet temperatures ranging from 50 to 500.degree. C. and space velocities ranging from 1,000 to 1,000,000 Nl reagents/L cat.times.h, reaching temperatures ranging from 450 to 1350.degree. C.