Effects of recombinant bovine somatotropln(${gamma}$BST) on hematologie and blood chemical values were investigated in twenty-five multiparous Holstein dairy cows. Recombinant BST was administered by two different routes ; intramusculary(12.5mg and 25mg/day) and subcutaneously(500mg and 750mg) in sustained-release vehicle every 2 weeks beginning 4 weeks postpartum and continuing for 7 months. Whole blood and serum samples were collected 0, 1, 2, 3, 5, and 7 months after beginning of treatments from control and ${gamma}$BST-administered groups. Hematologic values including RBC, PCV, HB, MCH, MCHC, WBC and differential counts of treatment groups receiving ${gamma}$BST were similiar to those of control group. Blood chemical values observed were total protein, albumin, A/G ratio, glucose, cholesterol, Ca, Pi, Ca/pi ratio, total bilirubin, creatinine, BUN, alkaline phosphatase, lactate dehydrogenase, alanine aminotransferase and aspartate aminotransferase. There were no significant differences in blood chemical values of cows administered with ${gamma}$BST from those of control. Although some blood chemical values were fluctuated at a certain observation period, they were remained within the normal physiological ranges. It is concluded from the observations of these experiments that the dose and dosage froms of ${gamma}$BST employed in this work might not affect hematologic and blood chemical values in dairy cows under the normal sanitary condition and adequate nutritional balance.