Studies about the vitamin metabolism in the field of dermatology were carried out by observing the skin manifestations of the vitamin deficient animals. The results of estimation of thiamine, riboflavin, pyridoxine and lipoic acid concentration in blood and urine of various skin diseases showed considerable number of cases being in a sense on the metabolic disorder with these vitamins : keratosis, ariboflavinosis, seborrheic dermatitis, etc., were clinically observed and discussed. The presence of vitamin B group in the skin was histochemically proved. Absorption, utilization and excretion of thiamine and lipoic acid labeled with ^<35>S were also investigated. Reports on the ascorbic acid metabolism related with the pigmentation of the skin, histochemically and electrocolorimetrically, observed were added.