28308.7mL。 Fermentation of raw materials can be mixed to make up for deficiencies of the single fermentation and in different degrees to enhance the effect of fermentation of raw materials. This research was carried out in controllable constant-temperature fermentation equipment. Cow dung, chicken manure and rice straw were selected with the proportions of TS ratio(0∶2∶1、0.4∶1.6∶1、0.8∶1.2∶1、1.2∶0.8∶1、1.6∶0.4∶1、2∶0∶1) as raw materials, and biogas fermentation at temperatures of 15℃,20℃,25℃and 30℃ was studied. The main conclusions were drawn as follows: the biogas production rate and cumulative biogas yield of each proportion rose with the increase of temperature; the fermentation period was longest at 15℃, but there were no difference among the other temperatures; the cumulative biogas yield was first increased and then decreased with the change of proportion, that was fermentation of a mixture of three types of raw materials——cow dung, chicken manure and rice straw, was significantly better than the effect of the mixture of cow dung and rice straw, as well as the mixture of chicken manure and rice straw, but no significant impact on the fermentation period. The model predicted, with the optimal combination of technology, the temperature of 30℃ and the TS ratio of cow dung, chicken manure and rice straw was respectively 1.22∶0.78∶1, the cumulative biogas yield was expected to reach maximum 28308.7 mL.