Objective To prepare reference materials of dioxins and dioxin-like polychlorinated biphenyls in fish powder matrix. Methods Using fly ash to feed grass carp, the fish samples were peeled, homogenized, dried, packed and sterilized. After homogeneity and stability studies, coordinated values were determined by 8 laboratories, and the uncertainty was evaluated. Results The reference material had good uniformity and the stability was more than 12 months. The characteristic values of PCDD/Fs were 0.017-1.4 pg/g, the expanded uncertainty were 0.02-0.6 pg/g and the characteristic values of DL-PCBs were 0.54-16 pg/g, expanded uncertainty were 0.28-6 pg/g. The matrix reference material was approved by the evaluation committee(GBW(E)100741). Conclusion The matrix reference material has good homogeneity and stability, which can be used in the quality control for analyzing, laboratory ability verification, analytical instrument calibration, analysis method accuracy evaluation and verification, etc.