Relevance. Currently, a meaningful role in the development of the pathological process in psoriasis is assigned to T-regulatory cells (Treg). A specific marker for Treg is the transcription factor Foxp3. Data on the dependence of the expression of Foxp3-positive cells on the severity and staging of the pathological process are contradictory. In this regard, it seemed relevant to study the expression of Foxp3+ T-regulatory cells in skin biopsies of patients before and after various treatment regimens, compare the data with the results of previous studies and conclude that it is possible to use this marker to evaluate the effectiveness of psoriasis therapy. Study purpose — to evaluate the expression of Foxp3+ T-regulatory cells in psoriatic plaques of patients with various immunosuppressive treatment regimens and, based on the data obtained, draw conclusions about the effectiveness of each of them. Material and methods. The 1st group included 32 patients who received narrow-band phototherapy according to the 4-day regimen, the 2nd group included 32 patients who received therapy with the sodium salt of gamma-D-glutamyl-D-tryptophan synthetic dipeptide, the 3rd group included 32 patients who received combination therapy with both of the described techniques. Results. The study showed that the amount of Foxp3+ cell fraction is significantly reduced in the skin biopsy samples of patients on the 21st day of treatment, the decrease was most pronounced in patients of the 3rd group. Conclusion. The level of expression of the marker of Foxp3+ T-regulatory cells with psoriasis decreases during therapy, thus reflecting its effectiveness, and also has a direct correlation with the PASI index and the volume of mononuclear cell infiltrate, its assessment can be considered as an additional criterion for the regression of the disease against the background of therapy.