The effectiveness of vaccine against dermatomycosis, caused by Trichophyton verrucosum, was studied in young cattle in three herds. The vaccines of Czechoslovak and Soviet production had almost the same effectiveness in prevention. In healthy calves without clinical signs of trichophytosis vaccinated at an age of one to three months with a dose of 2.5 to 5.0 ml, applied intramuscularly, and revaccinated with due respect to the rules of hygiene in the calf-houses, an incidence of 0 to 13% in the three- to five-month period of study was observed. In the non-vaccinated control groups, the incidence under the same infection conditions and in the same period was 36.3 to 100.0%. At the early stage of vaccination--during the inoculation of the animals suspected of being infected--the incidence of the disease was 50.0 to 68.8% and mostly showed no difference from incidence observed in the nonvaccinated control cattle. The therapeutic effect of the vaccine and Mykolastanox F is characterized by the fact that zero prevalence was obtained in the animals ten weeks after vaccination. Animals treated locally with Mykolastanox F showed zero prevalence 12 weeks after the beginning of treatment.