Dioxin like-polychlorinated biphenyls are unintentionally produced ubiquitous, persistent organic pollutants. The main source of human exposure to the compounds is food of animal origin because bioaccumulation in food chains. Extraction of dairy products by liquid-liquid extraction (LLE) technique for milk but extraction of other dairy products such as cheese was by soxhlet technique. In addition, clean samples after extracting the fat from dairy product samples by three - column chromatographyies, which include multi-layer silica, alumina column and then the third phase of the chromatographic column, is carbon. Method of analysis for determination of “dioxin-like PCBs" -show high toxicological properties that are similar to dioxins - in dairy products by high-resolution gas chromatography/ high-resolution mass spectrometry (HRGC/HRMS). Results were development of reliable and validated analytical method for dairy products, which recognized to be good indicator of environmental exposure for persistent organic pollutants. The method performance was tested for four non-ortho PCB congeners (PCB 77, 81,126, and 169) and eight mono-ortho PCB congeners (105, 114, 118, 123, 156, 157, 167, and 189) with good average recovery (via 13C12-labelled PCB internal standard) of the twelve PCB congeners for dairy products at level 40 ng/kg varies between 99-109 %. The trueness of a measurement method for dioxin like polychlorinated biphenyls in dairy product such as cheese where the results demonstrated satisfaction z-scores within range of ±2 for sum non-ortho-PCB was -0.85, and for sum mono-ortho-PCB -0.74. The reproducibility expressed as relative standard deviation percent was less than 22.6 % and the measured uncertainty including random and systemic error (on 95% confidence level) was less than 40%.