Abstract: Based on the principle of infrared measuring system,an approach to assessing clothing fabrics insulation under wearing condition by applying infrared instrument is put forward.Temperatures of a group of fabrics,made of different material,are examined,and their insulation performance are compared by this approach.Theoretical analysis and actual testing have proved that although there is no relationship developed yet between infrared and moisture transmission,starting from the clo of garment,the infrared imaging method,compared with the traditional one,is a convenient and an important tool for assessing thermal comfort property of clothing.