This paper regarded the three kinds of linen fabrics and clothing of unmodified and modified treatment as the research objects, measuring the fabric physical properties, doing the Subjective experiment and questionnaire survey. Physical properties test included water absorption, air permeability and moisture permeability; Wearing experiment was to determine the change of temperature and humidity on human body surface in a certain temperature- humidity condition and the state of motion, at the same time investigating the subjects about thermal- humidity comfort in a form of questionnaire survey. The experimental results show that modified flax fabric enhances the moisture absorption and moisture-penetrability, and weakens the permeability. Subjects of Wearing modified fabrics sense that the feeling of moist, stuffiness, clinginess and tickling is abating after exercise, showing that the permeability about thermal and humidity has been improved.