The aim: to set the peculiarities of bloodstream of the testis of white rat in normal condition and under the condition of experimental [artifi cial] diabetes course. Material and methods. The research has been conducted on 40 white mature male rats in the age groups 4.5 to 7.5 months with 130 to 150g of body weight. Research material is represented by ultramicroscopic testicle slice. Experimental diabetes modelling was performed through single intraperitoneal injection of Streptozotocin (“Sigma”, USA), dissolved in 0.1M citrate buffer, pH=4.5 (7mg per 100g of body weight of animals). The diabetes mellitus progression was controlled basing on glucose concentration in blood, which was measured by glucose oxidase test. In 2,4,6,8 weeks after experiment launch, animals in whose blood glucose concentration was above 13.4 mmol/l, were used for research. The selected trend of study is a part of a planned Science Department Anatomy “Structure bodies and bloodstream ontogeny, under the laser irradiation and pharmaceutical, blood circulation disorders, reconstructive surgery and diabetes”, state registration 0110U001854, performed at the Lviv National Medical University named Danylo Halytsky according to the state plan and program. University Animal Care and Use Committee Approval: № 8 from 18th of November 2013. Results. The fi rst signs of change of angioarchitectonics testicular were found on the second week of experimental diabetes. During the following terms bloodstream undergoes signifi cant changes. Vessels with irregular contours, winding in the lumen of blood clots found, the vessel wall is thickened, sklerozovana and stratifi ed. Around the vessels edema and haemorrhage are present. Available desolated areas of capillaries, in the lumens of some capillaries, the aggregation of red blood cells that cover the lumen of blood vessels are found. The lumen of the capillaries is narrowed. In the remaining capillary endothelial cells have the appearance of “standing column”, which is a characteristic feature of the hypoxic state of tissues. Capillary sclerosis, precapillary spaces are dilated. Conclusion. Changing in the diameter of the vessels of microvasculature endothelial is accompanied by swelling and change in the form of their lumen. Adhesion and aggregation of red blood cells are also observed. These changes show that angiopathy is a trigger hypoxia and as a result in 2 weeks of diabetes course micro and ultrastructural organization of the most convoluted seminiferous tubules varies.