The present investigation was undertaken to study the effect of different stages of lactation on erythrocyte osmotic fragility, blood leucocyte indices and milk somatic cell count in indigenous Badri cattle. Badri is first registered indigenous, dual purpose cattle breed of the state Uttarakhand (India) mainly reared in hilly areas of the state. Osmotic fragility evaluates the stability of erythrocyte membrane to osmotic stress. Leucocytes form defence mechanism against invading micro-organisms. Somatic cell count is an indicator of udder health. The study was carried out in forty healthy Badri cows divided into five groups according to their lactation stages viz. group 1 (0–60 days), group 2 (61–120 days), group 3 (121–180 days), group 4 (181–240 days) and group 5 (to be dried off). Erythrocyte osmotic fragility, blood total leucocyte count (TLC), differential leucocyte count (DLC) and milk somatic cell count (SCC) were estimated. The percent hemolysis of erythrocytes among different groups was significant (p < 0.05) at 0.9% and 0.5% saline concentrations. A significant effect (p < 0.05) of lactation stages on blood lymphocytes, neutrophils and milk somatic cell count was observed.