NOVELTY - Processing and converting food waste into fuel comprises: temporarily storing a leachate of food waste in an input hopper; crushing the stored food waste, and dehydrating in a screw press; separating the dehydrating food waste into a solid material and a supernatant; drying the supernatant in a dryer; temporarily storing the dried supernatant in a storage hopper; performing a heat exchanging process for the supernatant; separating an effluent from the supernatant; and separately collecting the heat-exchanged supernatant oil at optimum temperature.    USE - The method is useful for processing and converting food waste into fuel (claimed).    ADVANTAGE - The food waste is processed in cost-effective manner, and the oil, and the methane gas are separated and reused the respectively. The methane gas produced using a supernatant methane fermentation facility is used as the heating source, so that the supply and demand of the local energy is adjusted during the food disposal process.    DETAILED DESCRIPTION - Processing and converting food waste into fuel comprises: temporarily storing a leachate of food waste in an input hopper; crushing the stored food waste, and dehydrating the crushed food waste in a screw press with a compression process; separating the dehydrating food waste into a solid material and a supernatant; drying the supernatant in a dryer until the percentage of water content is 10%; temporarily storing the dried supernatant in a storage hopper; performing a heat exchanging process for the supernatant at 95-99 degrees C; separating an effluent which is oil, from the heat-exchanged supernatant; separately collecting the heat-exchanged supernatant oil at optimum temperature; heating the oil at 60-70 degrees C using the waste heat in a second heat-exchanger; separating water and the solid material from the oil using a solid-liquid separator; separating the solid material among the supernatant stored in a supernatant reservoir using a vibrating screen; performing a gas refining progress using moisture and hydrogen sulfide, and temporary storing the gas in a gas holder as fuel; and performing a methane fermentation process to produce the methane gas by disassembling the organic compound in a digester using an acid former and anaerobic methane bacteria.