TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The method comprises selecting, crushing, sieving and removing the components, non-biodegradable inert component and impurities more than 2 cm in the garbage to obtain the homogeneous garbage less than 2 cm, where the running range of the solid concentration of the material in the garbage filling region is 0-40%, the pH value of hydrolytic acidification is 4-9, the temperature is 30-60 degrees C and the retention period is 1-20 days. The form of the garbage entering into the garbage filling region is garbage, mixture of garbage and liquid waste, or mixture of garbage and semi-solid waste. The method comprises entering into the garbage filling region is disposable feeding, batch feeding or continuous feeding. The hydrolytic acidification comprises fermenting the insoluble materials in the particle state in the garbage to form the soluble hydrolytic acidification product, where the hydrolytic acidification product is organic polymer, organic monomer, organic acid and amine salt. In the step (c), the flow is 0-0.2 m3, the reaction time of the generated methane is 10-60 days, the reaction temperature of the generated methane is 30-45 degrees C or 50-60 degrees C, the pH value of the material flowing out of the microorganism bacterium agent filling region is 6.5-8.5. The microorganism bacterium agent in the step (c) is the agent rich in methane bacteria; and the content of the methane bacteria is 105-1013 per g. The material entering into the microorganism bacterium agent filling region in the step (c) is the material discharged from the garbage filling region, or the liquid or semi-solid material obtained by performing filtering or centrifugation treatment for the material discharged from the garbage filling region. The pH value of hydrolytic acidification in the step (d) is 4-9, the temperature in the step (d) is 30-60 degrees C and the retention period in the step (d) is 1-60 days. The repeated circulation process in the step (e) is not less than 30 times; and the upper limit of the circulation number is not more than 5 times per day; the maximal yield of the methane in the step (e) is 700-800 m3/t of the dry garbage organic substance. In the step (e), when the pH value of the liquid flowing out of the garbage filling region is more than 7, and the gas generation speed of the methane is less than 3 L.kg-.d-1, beginning to perform intermittent feeding for a new batch of the materials. In the step (e), when the pH value of the liquid flowing out of the garbage filling region is more than 7, and the methane content of the methane is more than 60%, beginning to perform continuous feeding. Preferred Components: The liquid waste is the waste having the solid content less than 5%, preferably poultry excrement, condensed sludge and wastewater in the sewage plant; or the semi-solid waste is the waste having the solid content of 5-20%, preferably the dewatering sludge in the sewage plant.