Germanium is one of the precious scattered elements in coal, also it is a typical dispersed element. Semiconductor germanium is the main raw material of the electronic industry. The determination of germanium in coal has important economic significance on the investigation and utilization of germanium resources. Factors that effect volatilization of germanium in coal in the process of ashing are discussed, which are average ramp up rate, ventilation conditions, coal quantity, thickness of coal seam and so on. Appropriate suspending agent gum Arabic is adopted, obtained color reaction time is 1 h. And the function of mixed acid is analyzed.