Abstract: The develcpment of biogas can gain widespread benefits. Quantitative results can be obtained, with the help of analysing comprehensive benefits of biogas construction by means of System Dynamics Model. In this paper, various benefits brought about by the develcpment of biogas, of a total of RMB 54 million yuan investment in a county lasting 20 years, are simulated dynamically. The results indicate that developing biogas can not only solve the shortage of rural energy but also is an important factor in advancing rural economy and improving ecological environment.The simulation results for different investment schemes are also compared in this paper.The analysis results by System Dynamics can make the corrprehensive benefits of biogas construction and the dynamical process and the tendency of the benefits variance understood qrantitatively and lively, and give a worthful reference for making develcpment policy.