In this study, a new design testing method for a wetsuit with knitted composite rubber at low temperature and high moisture environment, the impact of this test method. Composite fabric, POLYESTER, 4.55mm show all the best thermal insulation, dry irradiation light has resistant 10.14 ℃, wet irradiation light from wet to dry average warming 0.65℃/min averagely, using irradiation light at high moisture environment, composite fabric, POLYESTER, 4.55mm is 14.57 ℃, composite fabric, 8% SPANDEX, 40% POLYESTER, 52% NYLON, 4.23mm optimal cooling slope for dry insulation tester method 0.1℃/min, composite fabrics NYLON, 4.35mm method for wet insulation tester has the best cooling slope 0.18 ℃/min.