| With the energy restructuring in China, biomass energy with its advantages such as rich resources, cheap and easy to get, low-carbon and so on has been becoming an important part of energy structure. Biogas as one of biomass energy has been widely used in our production and life, which has significant energy, economic and ecological benefits. Anaerobic fermentation require strict anaerobic environment, factors of biopretreatment, inoculum-substrate ratio (ISR), total solid concentration, material, temperature, exogenous additives and so on have significant influence on anaerobic fermentation. In order to simulate biogas fermentation environment, controllable constant–temperature fermented equipment was used, manure and straw was chose as material. Factors that affect the anaerobic fermentation such as biopretreatment, inoculum-substrate ratio, total solid concentration, material, temperature, exogenous additives were studied. The main conclusions indicate that:1. The carbon and nitrogen ratio of straw decreased after biopretreatment. Among the agents of biopretreatment, biogas slurry was best. Biogas slurry was used pretreated wheat straw, rice straw and corn straw, and the optimal pretreatment time was 6d, 6d and 9d.2. At 25～35℃, the TS biogas production rates and TS biogas production yields of each ISR were first increased and then decreased with the increasing of temperature, the TS biogas production rates and TS biogas production yields were first increased and then decreased with the increasing of ISR. Multiple regression analysis predicted, at 36.6℃and the ISR is 0.24.3. At 40℃, when the total solid concentration was 20%, the biogas production yields of chicken manure was highest (17653mL); when the total solid concentration was 16%, the biogas production yields of wheat straw was highest (26855mL); when the total solid concentration was 16%, the biogas production yields of the mixture was highest (11733mL). The order of TS biogas yields was: 8%>12%>16%>20%.4. Single material: the biogas production efficiency of the pig manure was best, the TS biogas yield was 459.54mL/g; the biogas production efficiency of the human excrement was lowest, the TS biogas yield was 144.13mL/g; the biogas production efficiency of the corn straw was better than other straws, the TS biogas yield was 216.03mL/g. Mixture of pig manure and wheat straw, rice straw, corn straw, the biogas production efficiency of 1﹕1, 3﹕ 1, 2﹕1 were highest, the TS biogas yields were 327.46, 422.86, 413.71mL/g, respectively. Mixture of cow manure and wheat straw, rice straw, corn straw, the biogas production efficiency of 2﹕1, 2﹕1, 1﹕1 were highest, the TS biogas yields were 321.72, 274.96, 308.08mL/g, respectively. Mixture of chicken manure and wheat straw, rice straw, corn straw, the biogas production efficiency of 3﹕1, 1﹕1, 2﹕1were highest, the TS biogas yields were 325.22, 296.13, 284.47mL/g, respectively. Mixture of human excrement and wheat straw, rice straw, corn straw, the biogas production efficiency of 2﹕1, 2﹕1, 1﹕1 were highest, the TS biogas yields were 132.56, 168.75, 126.83mL/g, respectively. Mixture of pig manure, chicken manure and straws, the biogas production efficiency of 1.2﹕0.8﹕1 were highest, the TS biogas yields were 252.44, 253.53, 247.75mL/g, respectively.5. The best fermentation temperature of pig manure, cow manure, chicken manure were 30, 45, 50℃, the TS biogas yields were 468.60, 373.91, 355.28mL/g, respectively. The best fermentation temperature of wheat straw, rice straw, corn straw were 50, 45, 55℃, the TS biogas yields were 314.79, 364.22, 355.06mL/g, respectively. The best fermentation temperature of pig manure and straws mixture were 55, 35, 35℃, the TS biogas yields were 362.19, 416.80, 413.71mL/g, respectively. The best fermentation temperature of cow manure and straws mixture were 45, 50, 40℃, the TS biogas yields were 357.97, 345.50, 391.31mL/g, respectively. The best fermentation temperature of chicken manure and straws mixture were 45, 45, 50℃, the TS biogas yields were 344.47, 323.59, 389.93mL/g, respectively.6. Added urea and cellulose can increase biogas production yields, which were increased 2.46%～214.32% and 1.63%～104.28% than control, respectively.ISR and total solid concentration are important factors to anaerobic fermentation, when the ISR is 0.24 and total solids concentration is 8%, biogas production efficiency is highest. Different materials have different biogas production efficiency, and the biogas production efficiency of pig manure is highest. When straw is used as the main fermentation material, biopretreatment and co-digestion with manure can enhance the biogas production efficiency; and add urea or cellulose in mixed material during anaerobic fermentation, can further improve the biogas production efficiency. Biogas production efficiency of material is different at different temperatures, the optimum fermentation temperature rang of materials is between 30～55℃. Therefore, rural household biogas should be take some insulation or heating measures based on the actual situation of the facilities and materials.
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