Obesity as a leading preventable cause of death worldwide is closely linked to cardiovascular disease (CVD). Plasma plasminogen activator inhibitor (PAI)-1, a potent inhibitor of plasminogen activation and fibrinolysis, is increased in many clinical situations associated with high incidence of CVD. In the obesity-linked elevation of PAI-1, evidence points to TNF-alpha as an important regulator of PAI-1 expression in adipose tissue. Background: This study aims to evaluate mediastinal PAI-1 and TNF-alpha mRNA levels in adipose tissues (AT) and compare serum levels in obesity with and without coronary artery disease (CAD). Patients and methods: Obese patients with (n=37) and without CAD (n=20) were included in the study. Results: The serum levels of PAI-1 and TNF-alpha were significantly higher in obese patients with CAD compared to obese patients without CAD. PAI-1 mRNA expression was significantly increased in mediastinal adipose tissue (MAT) of obese patients with CAD compared to those without CAD, TNF-alpha mRNA expressions were found to be higher in EAT (epicardial AT), MAT and SAT (subcutaneous AT) of obese patients with CAD. Conclusions: The study demonstrated a close direct relationship between TNF-alpha and PAI-1. PAI-1 mRNA expression strongly correlated positively with serum TNF-alpha in MAT, and TNF-alpha expressions with PAI-1 serum levels.