The objective of the study is to obtain the basic data to establish the standard value of proper clothing weights in the change of thermal environment. For the purpose of this research, clothing weight and thermal sensation have been collected from 160 college student in Seoul and Kwangju area in April, July, October. Results are as follows : 1. Subjects were in Comfortable condition, particularly in Spring and Autumn. But in summer they were in warm condition and the case were reversed in winter when they were under cool condition. 2. The frequency of comfortable thermal sensation were low below 16.5 degree, above 27.5 degree, and were high between 16.5 degree and 23 degree on room temperature. 3. Generally, the positive correlation were found between clothing weights and thermal sensation. 4. Clothing weights and thermal comfort were as follows. Season : Spring, Autumn, Room Temperature(${circ}C$) : 16.3$~$23, Clothing Weights($g/m^2$) : 589.9$~$750.6, Season : Summer Room Temperature(${circ}C$) : 27$~$32, Clothing Weights($g/m^2$) : 362.4$~$432.5, Season : Winter, Room Temperature(${circ}C$) : 12.5$~$19.3, Clothing Weights($g/m^2$) : 913.7$~$1206.2