The hydroxyl fraction of cigarette smoke is studied by gas chromatography-mass spectrometry after trimethylsilylation. The smoke of three commercial cigarettes (2 American blend type and 1 dark type) is studied. 53 components are identified in this fraction, 4 of which (mannosan, erythritol, xylitol and threitol) were identified in cigarette smoke for the first time. Differences between these cigarettes could thus be demonstrated. The same method was subsequently used to study the pyrolyzate of cellulose, fructose, glucose and sucrose. This makes it possible to discuss the possible precursors of certain hydroxyl compounds of cigarette smoke.