Abstrakt. Abstrakt: Simmental bread belongs to two directional milk and meat usage cattle, because of its good musculature and beneficial size. The aim of the research was to determine the level of hematological parameters (RBC, WBC, Hb, Hct, PTL, MCH, MCHC, MCV), biochemical ones (urea, creatinine, uric acid, albumina, glucosa, ALAT, AST, all cholesterol, HDL, LDL i TG) as well as electrolytes (Na+, K+, Cl–) in pregnant cows blood. The material was collected from the simentaler breed cows at the age between 3 to 5 years, which were 2th to 7th months pregnant. Together 48 subjects were examined. All values of analyzed hematological parameters fitted the physiological standards. However red blood cells indicators were noticed to increase. Most the biochemical indicators showed some deviations from the physiological standards. Only the concentration of glucose and urine acid achieved recommended level. The level of electrolytes is also considered to fit the referential norm statistically significant differences were observed in the area of the examined values of haematological, biochemical parameters and electrolytes in cows being in different month’s pregnancy.