Economic feasibility of power generation system using waste woody biomass in a circulating fluidized bed combustor has been investigated. Effects of important variables such as capital investment, cost of waste wood, certified emission reduction(CER), system marginal price(SMP) on the benefit of business have been analyzed. Internal rate of return(IRR) was predicted as 16.67%, which implicates the business is promising based on the assumptions such as SMP of 99Won/kWh, capital cost of 10.65 billion won, and complimentary providing of waste wood. Major factors affecting the benefit of business were as follows; system marginal price, operational rate, capital investment, expenditure of waste wood, certified emission reduction. In addition, it must be necessary to consider CHP power plant providing steam as one of the means to diversify sales network, for the management of the business risk.