Alterations in the intracellular free Calcium regulation as well as disturbances of extracellular calcium homeostasis have been observed in patients with essential hypertension. Present study centers on estimating serum calcium level in patients with essential hypertension and establishing relationship between serum calcium level and severity of hypertension. In this study serum calcium levels were measured in 80 cases of essential hypertension which included 37 cases of grade I and 43 cases of grade II hypertension. The result showed that serum Calcium levels were significantly decreased in grade I (P<0001) as well as grade II (P<0001) hypertension cases when compared to age matched normotensive control. Furthermore, Grade II hypertension cases were having significantly lower serum Calcium level (P<0001) than grade I hypertension cases.