Abstract: The shape and fine structure of peripheral blood cells of Trionyx sinensis and its number and types in different seasons were studied. The results show that the number of erythrocyte and leucocyte is varied with seasons. The numbers of erythrocyte and leucocyte in August and May are increased respetively, and are decreased distinctly in hiberating stage (February).Neutrophils lymphocytes, thrombocytcs, basophils, eosinophils and monocytes occupy respectively 48, 20, 18, 6, 4 and 4% in leuorytes. The volume of its erythrocyte is larger. The leucocytes are stable to some acid and alkali elements.

Key words: Trionyx sinensis, Blood cell, Seasonal change, Shape and structure, seed germination, growth promoting, seedling growth and development, Trichoderma, antioxidant enzyme