The study of radiation-induced adaptation in yeast culture strain of Saccharomyces Сerevisiae was made. The yeast culture was contained in the nutrient medium of the composition with 4% sugar and 96% distilled water. Cell count was carried out using the Goryaev chamber. The results of the experiments were used to calculate the dose change factor. An adaptive response estimated by the dose change factor parameter was observed for the time interval of 2 weeks and 4 weeks. The function of the dose change factor versus time was built and function which describes the dependence with the value of approximation reliability R2 = 0.95 was chosen.