Objectives: To determine whether the analyzed Hypericum perforatum preparation has any kind of skin protecting or regenerating factors on human based model of irritant contact dermatitis caused by Sodium Laurylsulphate (SLS). Material and methods: The base of the study is randomised controlled trial carried out among 14 healthy adult examinees with no skin diseases in their medical histories. The research was conducted during 2019. at The School of Medicine in Split. By using Finn's chambers containing SLS, examinees were deliberately caused irritant contact dermatitis and the analyzed areas were their forearms. During the therapy two preparations were being used, one of them containing active substance (Hypericum perforatum), while the other was mere placebo. Effect of the questioned preparation was the amount of skin hydration, erythema, melanin and transepidermal water loss (TEWL) by using the instrument MPA 6 (Courage+Khazaka, Koln, Germany) with three probes (Mexameter, Corneometer, Tewameter). Results: The examined preparation based on H. perforatum did not show any statistically significant differences indicated on the measured skin parameters (skin hydration, erythema, melanin and transepidermal water loss (TEWL) in contrast to placebo. Conclusions: This research did not prove any effectiveness of Hypericum perforatum on improvement of skin barrier on human model with irritant contact dermatitis, experimentally caused by SLS. It will be necessary to conduct additional researches in order to gain conclusions which could objectively and clearly present the effect of H. perforatum on the examined skin parameters.