Background: Plasminogen activator inhibitor-1 (PAI-1) is mainly produced in the liver and in the adipose tissue. Normal fibrin clearance mechanisms were found to be affected by high plasma PAI-1 levels and thus increases risk of thrombosis. The aim of the current study was to expound the childhood obesity effect on circulating PAI-1 and interpret the relation of PAI-1 to metabolic syndrome. This cross-sectional study was conducted on 43 obese children following in the Children Hospital and compared to 44 healthy sex-and age-matched controls. All recruited cohort are subjected to anthropometric measurements: weight, height, BMI, waist circumference, hip circumference, and skin fold thickness (biceps, triceps, and subscapular), and laboratory investigations in the form of lipid profile, fasting blood sugar, fasting insulin, insulin resistance estimated by HOMA-IR, and plasminogen activator inhibitor-1. Results: The level of plasminogen activator inhibitor-1 in the obese group was significantly higher than that in the control group (47.98 ± 17.42 vs. 28.00 ± 11.35 respectively). PAI-1 showed positive significant correlation to anthropometric measurements: BMI (p = 0.000), weight (p = 0.000), biceps skin fold thickness (p = 0.04), triceps skin fold thickness (p = 0.4), and subscapular skin fold thickness (p = 0.04). Also, a significant positive correlation was found between PAI-1 and systolic (p = 0.000) and diastolic blood pressure (p = 0.04). Positive correlations were found between PAI-1 and cholesterol (p = 0.000), triglycerides (p = 0.02), LDL-c (p = 0.000), insulin (p = 0.000), and HOMA-IR (r = 0.5, p = 0.02). Conclusion: Fat mass accumulation is related to high PAI-1 levels, which might in turn contribute to cardiovascular risk. Plasminogen Activator Inhibitor-1 is a good predictive test for metabolic syndrome in obese children.