Studies done on internal jugular venous valve (IJVV) competence shows that structural and functional integrity of the IJV valve may be compromised when the IJV is cannulated for insertion of a central venous catheter. USG guided IJV cannulation distal and proximal from anatomical location of IJVV was carried out to study the incidence of IJVV incompetence. Methods: Sixty patients undergoing elective major surgery, without pre-existing incompetence of IJV valve were randomly divided in two groups high (distal) and low (proximal) to undergo IJV catheterisation (>1 cm above or below the cricoid level, respectively) under USG guidance. USG confirmation of IJVV status both, anatomical and physiological in normal respiration and with Valsalva manoeuvre was done. Color Doppler ultrasound was used to study the incidence of valvular incompetence at different intervals i.e. at (T1) preoperative, (T2) one week after catheter insertion and (T3) one month after catheter removal, both, during normal respiration and during Valsalva manoeuvres and were compared with baseline T1. Results: Incidence of IJVVI, with catheter in IJV (T2) was higher with lower approach than with higher approach (30% vs. 20%; p < 0.01) and tended to be so after removal of the catheter (T3) (20% vs. 13%; p =0.04). With Valsalva Manoeuvre, IJV diameter was significantly high in lower group at (T2), with catheter in IJV (H/L) (1.9+0.7/2.3+0.7*) and at (T3), after catheter removal (H/L) (1.9+0.8/2.3+0.9*). p <0.001. Conclusions: Cannulation and catheterization of the IJV may cause long lasting functional impairment of the IJV valve. IJV cannulation above the level of cricoid cartilage, under USG guidance helps to some extent in lowering the incidence of IJV valve incompetence.