Abstract: Background: Renal Artery Occlusion (RAO) induced hypertension is a major health problem associated with structural and functional modifications of the renal and cardiac vasculature. The present study was designed to investigate the antihypertensive activity of ethanolic extract of seeds of Linum usitatissimum (EELU) in RAO induced hypertensive rats. Materials and methods: Male Wistar rats (180-200 g) were divided in four groups Sham, RAO, EELU 200 mg kg-1 and EELU 400 mg kg-1. Treatment group were pretreated with EELU (200 and 400 mg kg-1) for 4 weeks. After that on last day of the experiment, left renal artery was occluded with renal bulldog clamp for 4 h. The right carotid artery was cannulated, renal clamp was removed and immediately subjected to hemodynamic recording and assessment of left ventricular function. Results: RAO group significantly increased hemodynamic parameters at 15, 30 and 45 min of clamp removal. EELU (400 mg kg-1) treated group significantly decreased hemodynamic parameters at 15 min after clamp removal which remained for 60 min. EELU (400 mg kg-1) treated group showed significant improvement in left ventricular function at 15, 30 and 45 min of clamp removal. The flow cytometric analysis showed significant decrease in Reactive Oxygen Species (ROS) production by renal cells in EELU (400 mg kg-1) treated group as compared with RAO group which indicated antioxidant activity of EELU. Conclusion: It is concluded from the present investigation that the antihypertensive activity of EELU may be resulted through the action on rennin angiotensin system and inhibition of ROS.