The friction between the skin and fabric surface is an important parameter characterising the comfort performance of garments. In this study, the effect of moisture on the friction coefficient of knitted fabrics containing different elastane ratios was investigated. The measurements were carried out by means of the FRICTORQ tester, a new patented measuring instrument developed at the University of Minho and based on a new method of determination of friction coefficient of fabrics. It was found that with increasing moisture level in fabrics, the friction coefficient increases as well, but just to a certain limit. The level of friction coefficient becomes stable over the moisture regain value of 40%. The fabrics which contain elastane yam in every alternating course and the tight structures exhibit the highest fabric friction values.