Calcieum level management in the transition period is one of the most important factors affecting the performance of dairy cattle. There are limited studies on the relationship between dairy cow’s hypocalcaemia of dairy cattle and the performance and health of newborn calves. The aim of this study was to investigate the relationship between cows hypocalcaemia and newly born Holstein calves. thus we used from 40 Holstein cows that were divided into two groups of low calcium (LC) ( 8 mg / dl) and high calcium (HC) ( 8 mg / dl) based on calcium level measured at calving. Weight performance and dry matter consumption of starter were measured for till 70 d after parturaition 10 days apart. Respiratory rate and stomata were scored daily. The level of total protein, white and red blood cells and platelets were evaluated in the serum of calves at d 70. At the end of the 70-day period, calves belonging to group of high calcium had higher weight of 3 kg and an average of 0.5 kg of starter (P 0.05). Respiratory problems were 6 times higher in hypocalcaemia calves (P 0.05). Also, the frequency of stool score above 3 was higher in this group of calves (P 0.05). In the first 24 hours, total protein was higher in the high calcium group (P 0.05), but the ratio of neutrophil to lymphocyte at the end of the period was higher in the hypocalcaemia group (P 0.05). In general, calves belonging to hypocalcaemia cattle were weaker in function, and also stimulate the immune system and exacerbate diarrhea and respiratory problems . Keywords: Holstein calf, hypocalcaemia, growth performance, health, immune system.