Probiotics improve the immune system. However, the effects of its lactic acid bacteria on atopic dermatitis relief and inflammation improvement is not fully understood. Recently, one of the probiotics, Lactobacillus helveticus HY7801 (HY7801), was found to have an anti-inflammatory effect. In this study, we investigated the effects of HY7801 on atopic dermatitis-induced animal models. After four weeks of oral administration, the group treated with HY7801 showed amelioration of the atopic dermatitis compared to the group receiving placebo. In the HY7801 treated group, the epidermal hyper-proliferation and collagen deposition were inhibited compared to the placebo group, and the secretion amount of the inflammatory factors, such as TNF-α, IL-4 were reduced. In conclusion, these results suggest that HY7801 acts as a functional probiotic via amelioration of the atopic dermatitis such as a decrease of epidermal hyper-proliferation, and collagen deposition and anti-inflammatory effects.