PURPOSE:To describe the hematologic values of male and female, young and adult, Swiss mice (Mus musculus).METHODS:Mus musculus (n=14) were randomly selected and separated by gender. The male and female, young and adult animals were sedation to obtain a blood sample, by intracardiac route at 30, 45, 60, 75, 90, 105 and 120 days after birth.RESULTS:The Swiss mouse hemogram values obtained, in relation to total eosinophils, basophils, and number of platelets, there was no statistical differences according to the genders or the age of the animals. Regarding the erythrocyte, hemoglobin and hematocrit values obtained, these were higher in females. The RDW-CD and MPV values were higher in the females than in the males.CONCLUSIONS: Lymphocytes are the predominant cells in the peripheral blood. The collection of 800 µL of blood by intracardiac route, every 15 days, did not affect the health of the animals. Analyses of the blood samples contribute to the experimental models provided by the Central Animal Facility of UFMS and used by professors.