NOVELTY - A mixture of a hydrocarbon fuel, an oxygen rich gas and steam is supplied to a reactor having a catalyst bed containing specific catalyst. The fuel, oxygen rich gas and steam are pre-heated at 380-450degreesC. The pre-heated mixture is contacted with catalyst bed at a gas hour space velocity of 25000 h-1 or more. Exothermic combustion reaction and endothermic steam reforming reaction are preformed to obtain hydrogen-rich synthesis gas.    USE - For thermo-neutral reforming for producing hydrogen-rich synthesis gas from liquid hydrocarbon fuel, used as feed for on-board reformer in vehicles incorporating high temperature or low temperature fuel cell, as feed for hydrogen enrichment in internal combustion engines, and in stationary applications (all claimed), and for hydrocarbon to liquid conversion, methanol production, hydrogen feedstock for hydroprocessing, and production of high pure hydrogen and chemicals. Fuel cell includes proton exchange membrane fuel cell, solid oxide fuel cell and molten carbonate fuel cell.    ADVANTAGE - The thermo neutral reforming of liquid hydrocarbon fuel is efficiently performed using a single catalyst capable of performing both combustion and reforming. The deactivation of catalyst due to formation or sulfidation of coke by action of catalyst function of hydrogen and oxygen is prevented.    DETAILED DESCRIPTION - A mixture of a hydrocarbon fuel, an oxygen rich gas and steam is supplied to an interior zone of a reactor having a catalyst bed. The catalyst bed consists of a Ni-Ce2O3-Pt-Rh combined combustion and steam, and/or carbon dioxide reforming catalyst. The fuel, oxygen rich gas and steam are pre-heated at 380-450degreesC. The pre-heated mixture is contacted with the catalyst bed at a gas hour space velocity of 25000 h-1 or more. An exothermic combustion reaction at reaction temperature of 800-900degreesC and an endothermic steam reforming reaction for a period of time to reform liquid fuel are preformed to obtain a hydrogen-rich synthesis gas.    DESCRIPTION OF DRAWING(S) - The figure shows the schematic view illustrating the thermo neutral reforming process.