Back-ground: Preeclampsia, a systemic illness of late pregnancy seen in approximately 6% of primigravid women, is an important cause of maternal & fetal morbidity. The levels of calcium and magnesium in pregnancy may implicate in their possible role in pregnancy induced hypertension. This study assessed serum Ca2+ , Mg2+, Na+ and K+ levels in women with PIH (pregnancy induced Hypertension) and Preeclampsia compared with normal pregnancy. Material & Methods: This study was conducted on 100 pregnant women as a control & 100 pre-eclamptic women as a study group. We evaluate the serum potassium, sodium, magnesium, calcium levels in both the group. Result: The result of this study we found evaluated serum potassium level as compared to control it is significantly higher. Calcium, Sodium, Magnesium are significantly low. Conclusion: In the light of the above observations, it can be concluded that Pre-eclamptic pregnant women have higher levels of S. Potassium decreased level of S. Calcium & Magnesium and no significant difference in Sodium levels as compared to normotensive pregnant women in their IIIrd trimester pregnancy. Lowered plasma or serum Magnesium concentrations in pre-eclampsia may contribute to the development in hypertension in pregnancy. In addition, a disturbed Calcium homeostasis is observed in pre-eclampsia.