The authors treated the apigmented melanoma IC-Sofia in hamster with various doses of the following cytostatics: Cyclophosphamide, 6-Mercaptopurine, Vinblastine and Actinomycin D for 7 consecutive days. Determination of the tumor growth inhibition on the 8th day (early test) on the basis of tumor weight in the animals treated and untreated with cytostatics indicates that the tumor used is more sensitive to the effect of Cyclophosphamide and 6-MP and less to Vinblastine and Actinomycin D. Nevertheless sensitivity to cytostatic action is high enough for each of the cytostatic agents, depending upon the applied dose. This gives grounds to the authors to assume that hamster apigmented melanoma IC-Sofia is an adequate model for testing and evaluation of antitumor drugs.