An automated clean-up system was validated for simultaneous analysis of polychlorinated-dibenzo-p-dioxins(PCDDs), polychlorinated-dibenzo-p-dibenzofurans (PCDFs), and co-planar biphenyls (PCBs) in certified reference materials (CRM, fish sample). After Soxhlet extraction, 3 CRM fish samples were clean-up by automated fluid management system Power Prep. Quantitation of target compounds was conducted by HRGC-HRMS and isotope dilution technique.The average recovery of ~ ~13 C-labeled compound ranged from 62.4% to 84.3% for PCDD/Fs and from 53.1% to 89.2% for PCBs. All TEQ values obtained from the 3 CRM fish samples were comparable with their certified values, which indicate that it is suitable for trace analysis of PCDD/Fs and coplanar PCBs.=