NOVELTY - Preparing a direct carbon fuel cell from catalyzed carbon comprises: drying a mixture of raw materials whose grain is millimeter-sized or micron-sized by crushing at 70-100 degrees C; and putting the raw materials in a tubular coking furnace in anaerobic or anoxic environment, treating the raw materials by coking and thermal decomposition at medium-high temperature of 400-800 degrees C, cooling the raw material, and obtaining a carbon fuel with autocatalysis performance, where the raw material mainly comprises a biomass in a waste carbon element, the reproducible biomass plant straw, wood fiber.    USE - The method is useful for preparing a direct carbon fuel cell from catalyzed carbon that is used in an environment protecting fuel technology.    ADVANTAGE - The direct carbon fuel cell is prepared with an amorphous structure with large specific surface area, is easily soaked in a fused carbonate bath. The carbon fuel particles have lots of metal ion functional groups on the surfaces so that the activation and catalysis of carbon oxidization reaction are enhanced.    DETAILED DESCRIPTION - Preparing a direct carbon fuel cell from catalyzed carbon comprises: drying a mixture of raw materials whose grain is millimeter-sized or micron-sized by crushing at 70-100 degrees C; and putting the raw materials in a tubular coking furnace in anaerobic or anoxic environment, treating the raw materials by coking and thermal decomposition at medium-high temperature of 400-800 degrees C, cooling the raw material, and obtaining a carbon fuel with autocatalysis performance, where the raw material mainly comprises a biomass in a waste carbon element, the reproducible biomass plant straw, wood fiber and other reproducible biomasses rich in carbon, and the waste is waste paper, waste plastic, disposable packaging material and other carbon-rich waste, and the anaerobic or anoxic environment is provided by protective gas such as nitrogen, argon, helium or direct carbon fuel cell anode tail gas generated by carbon dioxide.