Abstract: Based on sensitivity analysis methods, the paper makes economic benefits evaluation to large-scale pig farm biogas project, take Jian ou Jian Hua Co., Ltd. Qingzhou pig farm as an example .The results showed that: the economic benefits of large-scale pig farm biogas projects is sensitive to government subsidies, as well as the the utilization of biogas, biogas slurry and residue, which should be adopted to improve the utilization of by-product of biogas projects, as well as increasing the intensity by means of fiscal policy to support large-scale pig farm biogas projects to promote the sustained and healthy development.