Abstract: Introduction: Pre-eclampsia and Eclampsia is one of the major cause of maternal mortality and morbidity. These conditions are largely preventable once detected, and are treatable. Defective placentation and endothelial dysfunction leading to endothelial cell injury are considered as the core features of preeclampsia .Lactate dehydrogenase (LDH) is an intracellular enzyme and is responsible for interconversion of Pyruvate and Lactate in the cell. Several studies report that serum LDH level increases with severity of preeclampsia and shows significant correlation with high blood pressure and poor maternal and perinatal outcomes. Studies have shown that LDH activity and gene expression are higher in placentas of pre-eclampsia than normal pregnancy. They serve as indicators suggestive of disturbance of cellular integrity induced by pathological conditions and are used to detect cell damage or cell death. Objectives: To correlate level of LDH with severity and complications of preeclampsia and associated maternal and perinatal mortality and morbidity. Material and Methods: An observational prospective study was conducted on 150 pregnant women in department of obstetrics and gynaecology, JNMCH AMU Aligarh U.P. Serum LDH was measured by continuous spectrophotometric method. Results: Higher levels of LDH was found in women with preeclampsia and eclampsia as compared to normal pregnant women. Maternal complications and adverse perinatal outcome were maximum in women with LDH>800 IU/L. Conclusion: LDH is an important prognostic marker of pregnancy induced hypertension. Elevated LDH levels may be considered as severe feature of preeclampsia.