The purposes of this study are finding out thermophysiological properties throughout wearing experiment with standard cooling vest as well as providing data in order to design and apply more comfortable cooling vest. To do this study, we produced cooling vest newly. 1. Rectal temperature was ascended approximately from $37.2^{circ}C$ to $38.05^{circ}C$ in lab, but wearing cooling vest, the temperature was descended 0.2 while wearing developed product compare with existing product. Mean skin temperature which was showed distribution from $32.8{sim}36.5^{circ}C$, it was descended $1.0{sim}1.1^{circ}C$, while wearing cooling vest and comparing with existing product, wearing developed product was lower $0.5^{circ}C$. 2. While wearing developed cooling vest, it was found that they had lower tendency than standard cooling vest. Specifically in case of temperature within clothing (chest) $0.2{sim}2.0^{circ}C$ in case of humidity within clothing 2~8%RH. Facts from above we confirmed that clothing microclimate had been improved and space was happened between body and garment in order to control. 3. In subjective sensation, standard cooling vest made negative response during experiment period from participants, but new cooling vest was nearing to comfortable area. It was con finned from above conclusions that wearing developed product is more effective in terms of comfort and reduction of heat stress in situation of working in hot environment.