This study was carried out to examine the formation and the emission status of PCDDs/PCDFs (Polychlorinated dibenzo-p-dioxin/Polychlorinated dibenzofurans) in the flue gases of MSW (municipal solid waste) incinerators. The formation concentrations of PCDDs/PCDFs generated at the outlet of SDR(Spray Drying Reactor) were in the average 0.142 ng-WHO-TEQ/Nm3 (0.140 ~ 0.143 ng-WHO-TEQ/Nm3), while the emission concentrations at the stack were in the average 0.027 ng-WHO-TEQ/Nm3(0.004 ~ 0.066 ng-WHO-TEQ/Nm3). Also, the removal efficiency of PCDDs/PCDFs has been analyzed by 53 % to 97 %(Activated carbon injection 0 mg/S㎥, 35 mg/S㎥, 70 mg/S㎥) were satisfied with both dioxin emission standards 0.1 ng-TEQ/Nm3 at AC 35 and AC 70.