In this study, fixed bed type CO2 gasification reactor was tested to enhance the production of synthetic gas (CO + H2) from low grade carbon source such as sewage sludge, wood chip, municipal waste, and low calofic valued coal. Various parameter effects on the 0.1 ton/day fixed bed gasifier operation were investigated. The parameters are reaction temperature, CO2/Air ratio, and total flow rate. Temperature was measured at the inlet and outlet of the reactor as well as at 18 positions along the reactor height and radius. The CO2 inlet concentration was tested between 0% and 30%. Total flow rate was varied from 40 L/min to 80 L/min at 20% CO2 inlet and 8 kg activated carbon packing. In the fixed bed CO2 gasification, CO2 took more parts in the gasification than combustion. But CO2 concentration higher than 40% made the two reactions unstable and the one between 20% and 40% did not give so much influence on the reaction time. The reaction time was shortened according to the total flow rate increase, and changed its slope gently above 50 L/min, illustarting CO2 gasification reaction is superior to combustion reaction in the low total flow rate condition.