1) Cotton diapers covered respectively with non-transporting synthetic water-proof cloth (NC), moisture-transporting water-proof cloth (MC), air-transporting water-proof cloth (AC), and wool flannel (WC), were worn inside dressings in sitting posture. Temperature and humidity inside diapers were measured, at front and back, and the diapers were weighed before and after tests to obtain weight-change, which was then compared with the result of our previous experiments on disposable diapers (non-transporting (ND) and moisture-transporting (MD)). The order of humidity inside diapers at 30°C were ND > NC > MD > WC _??_ MC _??_ AC. The correlation between final humidity inside diaper and weight-change was 0. 82. 2) ND, MD, and WC in dry and wetted states (with 10, 20, 40 g of water) were worn under beddings in lying posture for 7 hr. As to dry materials, the weight increased highly in ND, and in lesser degrees in MD and WC. As to diapers wetted with 40 g of water, wet-remain was 90 % in ND, 50 % in MC, and 10 % in WC. 3) Dry ND, MD, and WC were worn under beddings in lying posture for 3. 5 hr. Humidity was measured at front, back, and gluteal cleft. The result was ND >MD > WC, and in each case humidity was highest at the cleft. The correlation between final humidity inside diaper and weight-change was O. 99. Weight-change test proves trustable. Gluteal cleft is found to be an important spot for the measurement.