Turner's syndrome (TS) is a genetic disorder caused by numeric and/or structural abnormalities of the X chromosome. In a previous study it was observed that acne is less frequent in TS than in the general population. Since the onset of acne in pre-pubertal or pubertal age is related to sebum production, this study evaluates sebum secretion in TS patients, comparing the results with those of a control group of age-matched healthy female subjects. A total of 22 patients affected by TS (mean age 26.56 +/- 7.89 years) and a control group of 23 age-matched healthy females were studied. Sebum production was measured using a Sebumeter SM810. Mean sebum secretion in TS subjects was significantly lower than in the control group (81.35 +/- 66.44 UA vs 147.09 +/- 33.62 UA, p < 0.001) and this significant difference was found in every facial zone. The reduction of sebum secretion may explain, using a simple and non-invasive method, the absence or the low incidence of acne in TS patients.