In recent years, because the dry skin problem has become very common, it is getting the more important to preserve the barrier function of the skin. Although protecting the skin against water loss is one of the representative factors of its barrier capabilities, there is no report until now about the relationship between daily use of bath liquid and the moisture-keeping capacity of the skin.   In this study we examined how the skin condition can be improved after 14 straight days of employment of our bath liquid ‘Ulmore®’including Polyquaternium-10 and several moisturizing ingredients. Polyquaternium-10 is a Cationized Cellulose and is widely formulated in shampoos and hair conditioners.   We found that the application of Ulmore® for 10 or 14 days significantly maintained sratum corneum water content (SCWC) and transepidermal water loss (TEWL) compared with the placebo application. This result suggests that this is because our bath liquid covered the stratum corneum and protected the skin from water loss caused by the environmental factors like low humidity.   Thus we conclude that daily use of the bath liquid has a beneficial effect on skin moisture.