The paper presents the data on morphofunctional specificities of blood leucocytes in different Canidae species (mink, polar fox, silver fox and raccoon dog) bred in captivity in Karelia. Differences in blood composition, morphology and activity of leucocyte alkaline phosphatase in some carnivores and in comparison with herbivores were demonstrated. It was established that raccoon dog differs significantly from other species of Canidae fur animals.