Abstract: In order to explore the quantitative relationship between formation of sulfur dioxide from sulfur in coal and heating temperature, a study is made of the state of occurrence of sulfur in each component of coal, thermogravimetric curve of coal and infrared spectrum of sulfur dioxide, by means of X-ray photo electron spectroscopic meter(XPS) thermogravimetric analyzer-Fourier transform infrared spectrometer(TGA-FTIR) and intelligent Coulometric sulfur analyzer( CSA), together with the testing on emission of sulfur dioxide from coal at different heating temperatures. Result of study shows that there exists a quantitative relationship between emission of sulfur dioxide and temperature and it is related to occurrence form of sulfur in coal; the temperature required for the emission of SO₂ varies depending on the forms of sulfur: organic sulfur(<400 ℃), pyrite sulfur(400~900 ℃)and sulphate sulfur(>900 ℃). The research-derived result is of great significance for sulfur removal and rapid checking of forms of sulfur in coal.