Thermal pyrolytic behaviour of different types of tobacco leaves, such as flue-cured, Burley and oriental tobacco were investigated using double-shot pyrolysis-GC/MSD methods. Three grades of flue-cured tobacco and Burley tobacco, and three origins of Oriental tobacco were pyrolyzed over seven discrete temperature ranges with an interval of 50°C, from 100°C to 450°C with a heating rate of 50°C/min. Total ion chromatograms of pyrolysate of each of the temperature ranges showed different pyrolytic patterns due to different tobacco types and grades. Pyrolysis of temperature range from 150°C to 200°C and subsequent from 200°C to 250°C gave a distinct result among different types of tobacco leaves. In the case of higher temperature ranges, from 300°C to 350°C and subsequent temperature range from 350°C to 400°C, there were less distinct results between different tobacco types. With thermally evolved components such as nicotine, neophytadiene, furaneol, hydroxymethylfurfurole, megastigmatrienone, palmitic acid, and so forth, the principal component analysis gave different statistical distances among different types of tobacco leaves depending on the tobacco types, grades and temperature ranges.