Background: Preeclampsia is characterized by an imbalance in angiogenic factor, including soluble endoglin. Serum soluble endoglin levels were significantly different in patient with preeclampsia than in healthy pregnancy. Aim of the work: Evaluation of the increased level of serum soluble endoglin in preeclampsia and normotensive pregnant females.Patients and Methods: Forty pregnant female of at least twenty weeks of gestation were included and divided into two equal groups; preeclamptic and non preeclamptic group. 5ml of blood were collected by venipuncture into test tube without anticoagulant. Plasma endoglin was assayed by one-step sandwich enzyme immunoassay using monoclonal antibodies to human endoglin using kits.Results: preeclampsia group had higher endoglin level compared to normal one with statistically highly significant difference 18.52 ± 9.54 versus 2.2 ± 1.4 (p= 0.000) and elevated serum soluble endoglin showed a significant +ve correlation (r=0.523, P=0.016) with a risk of pre-eclampsia. With the highest positive predictive and lowest negative predictive values, a cutoff point of 6.26500 ng/ml had the best sensitivity and specificity. Conclusion:Serum soluble endoglin has a remarkable accuracy for diagnosis of preeclampsia.