Abstract: A quantitative analysis method for He, Ne, N₂, CH₄ and CO in fuel simulation gas hydrogen of fusion reactor by the micro gas chromatography was established. The effects of column temperature, pressure and injection time on the analysis of the impurities in hydrogen were studied. The detection effect of the micro gas chromatography to the trace impurities was investigated. The results indicate that the method can quickly realize the separation of the impurities in hydrogen, and can quantitatively detect scores ppm of CH₄, which can meet the impurity analysis requirements of the tritium plant. It’s a speedy, accuracy and applicable quantitative analysis method.