Background: One of the most important pregnancy problems is pre-eclampsia (PE). PE is caused by changes in the circulating levels of angiogenic agents. Endothelial dysfunction is caused by elevated levels of antiangiogenic factors like soluble fms-like tyrosine kinase-1(sFlt-1) and decreased levels of angiogenic factors like placental growth factor (PlGF). Objective: This study's objective is to assess the significance of alternation of angiogenic balance as a preeclamptic marker and their association to PE severity. Patients and Methods: One hundred pregnant women in third trimester participated in this case-control study, with 40 having mild PE, 40 having severe PE, and 20 healthy pregnant ladies as control. It was done in Clinical Pathology and Obstetrics and Gynecology Departments of Mansoura University Hospitals during a period from "November 2020 to April 2022". Clinical and laboratory tests on all individuals were performed, including CBC, LDH, sFlt-1 in the serum, PLGF, liver function tests, renal function tests. Results: In comparison to the control group, greater levels of sFlt-1 and sFlt-1/PLGF and lower levels of PLGF were present in all cases of mild and severe PE (p0.001 for each). Additionally, severe cases demonstrated significant high levels of sFlt-1 and sFlt-1/PLGF and significant low levels of PLGF with superior AUCs when compared to moderate instances (AUC=0.999). Conclusion: sFlt-1, PLGF and sFlt-1/PLGF ratio may have a role in the prediction of severity of PE, and thus diagnosis of PE, thus may be used in management of PE.