Perioral dermatitis is a facial skin disease with insuffciently studied ethiology and pathogenetic mechanisms, being one of actual problems of dermatology. It is a chronic relapsing facial skin disease mainly in women of young and middle age (in men and children meets less often). The disease has an independent clinical picture which is different from rosacea, demodecosis, seborrheic dermatitis, etc. The standard diagnostic criterion is a visual estimation of expression of an infammation on the basis of signs of exudative reaction which has a subjective character. Possibilities of a radiometric method for an objective estimation of a facial skin functional condition and indicators of an intracellular metabolism in patients with a perioral dermatitis were frst studied.