Abstract: This paper shows the frequency of each reflectance interval and the method of generating a vitrinite reflectivity distribution chart of mixed coal based on histogram generation principles and the vitrinite reflectivity distribution of single coal. It calculates average vitrinite reflectance（Rr） and standard deviations（S）of mixed coal under different ratios and generates a vitrinite reflectivity distribution chart so to save time and cost of laboratory work，which could be widely applied in coal blending and coking-coal mixing process.

Key words: Vitrinite, Reflectance, Distribution chart, Half-order, Frequency, Coal blending