A multi-functional gas chromatograph gas path flow, the gas path flow uses two inlets, three chromatograph columns, one two-arm thermal conductivity detector, two hydrogen flame detector, and two inlets parallel connecting to the carrier gas inlet, behind the first inlet, parallel connecting two chromatograph columns, one chromatograph column linking the hydrogen flame detector, another chromatograph column linking the nickel catalyst furnace and the second hydrogen flame detector through the first arm of the thermal conductivity detector; the second inlet followed by the third chromatograph column and the second arm of the thermal conductivity detector. The invention using one thermal conductivity detector, two hydrogen flame detectors, to process oil dissolved gas analysis, a sampling can complete seven gases analysis, simple operation and short analysis time; when processing oil gas content analysis, the gas path need not any changes, two times sampling can complete nine gases analysis, and it can process not only oil dissolved gas analysis in the electricity transformer, but also oil gas content analysis.