NOVELTY - Agricultural waste is treated by collecting agriculture and forestry wastes, performing centrifugal dewatering, breeding, mixing, storing and sealing in horizontal double-layer tube aerobic fermentation tank, fermenting, aerating, and controlling temperature at 65-75 degrees C, conveying mixture to horizontal aerobic fermentation tank for secondary aerobic fermentation, aerating, and controlling temperature at 50-60 degrees C to obtain mixture containing not greater than 30% moisture, crushing mixture, sieving to obtain organic fertilizer of not greater than 0.5 cm particle size, homogenizing, storing, and packaging.    USE - Treatment of agricultural waste for preparing organic fertilizer and biogas (claimed).    ADVANTAGE - The method is simple, low cost, and highly automated, facitates large waste capacity, consumes less time in fermentation step, and has uniform degree of fermentation, and treatment is done in enclosed system thus bad smell is not exposed in the atmosphere, and purified biogas can be sold in the market, and be used as source of energy for combustion, and organic fertilizer, and liquid fertilizer has high market value.    DETAILED DESCRIPTION - Treatment of agricultural waste involves collecting agriculture and forestry wastes containing not less than 70% moisture, performing centrifugal dewatering, breeding to not greater than 70% moisture content, mixing to obtain mixture containing 55-65% moisture, storing and sealing in horizontal double-layer tube aerobic fermentation tank, fermenting, aerating, and controlling temperature at 65-75 degrees C, conveying mixture to horizontal aerobic fermentation tank for secondary aerobic fermentation, aerating, and controlling temperature at 50-60 degrees C to obtain mixture containing not greater than 30% moisture, crushing mixture, sieving to obtain organic fertilizer of not greater than 0.5 cm particle size, homogenizing, storing, and packaging.    DESCRIPTION OF DRAWING(S) - The drawing shows a process flow diagram of the treatment of agricultural waste for preparing organic fertilizer and biogas. (Drawing includes non-English language text).