To study the feasibility of developing coalbed methane in coal mine and give guideline to application of this technology in coalbed methane development and gas control in coal mine, this paper evaluates the coalbed methane resource of Guanzhai coal mine based on its geology. Guanzhai coal mine has favorable geology and reservoir for coalbed methane with abundance of coalbed methane. Reservoir simulation software was used to forecast the single well gas production with result showing a higher rate, up to 932.00 m3/d in continuous 15 years. Gas from No.4 and No.9 coalbed decreased by 33.93% and 33.33%. Guanzhai coal mine has potential of large scale production of coalbed methane, and relatively safe. This feasibility study, combining geology and resource potential with production forecast, is effective in simulating coalbed methane in coal mine.