The concentration and the distribution of dioxin-like PCBs were studied by analysing the bottom ashes and the fly ashes from municipal waste incinerators in Seoul. The concentration of dioxin-like PCBs in the bottom ashes were detected 828.31, 908, 862.55pg/g dry weight and those in the fly ashes with 1207.64, 1908.88, 2182.26pg/g dry weight, respectively. I-TEQ concentration of dioxin-like PCBs in the bottom ashes were 8.14, 9.41, 8.6pg-TEQ/g dry weight and in the fly ashes with 18.57, 24.27, 12.87pg-TEQ/g dry weight, respectively. In case of the average concentration of isomer, the bottom ashes was as much as the fly ashes about 77-TCB. 105-PeCB had the highest value in the case of bottom ashes, and 118-PeCB in the case of fly ashes.