Pajamas are worn for long hours in direct contact with one's skin; so we assume that the contact sensation of the material of pajama cloth might influence the quality of one's sleep. In this study, we looked at pajamas made of RAFUMA-mixed cotton cloth, which is called “Wearable Chinese medicine” which is said to be good for one's health, and studied clothing comfort through wearing experiments. Subjects wore RAFUMA-mixed cotton pajamas (A) and nylon-mixed cotton pajamas (B) alternately. Their biological reactions were measured and subjective examinations were also performed. In Wearing Experiment (I), the subjects' EEGs were measured for 30 min when wearing pajamas. In Wearing Experiment (II), subjects' hormone secretion levels and skin temperature during normal sleep were measured. The EEG measurement results showed a significantly high ratio of α-waves when the subjects were wearing pajamas (A), proving that the subjects were in a state of relaxation at the time. It was also observed that melatonin secretion was promoted and small skin temperature differences occurred between the trunk and peripheral regions. From these observations, it is suggested that one can obtain effective sleep while wearing pajamas (A). The biological reactions observed while subjects wore RAFUMA-mixed cotton pajamas coincided with the results of the subjective examinations on wearing comfort and feeling of sound sleep.