Background: Central vein cannulation (CVC) in pediatric patients with congenital heart disease is a challenging task due to unpredictable altered anatomy. So the means to improve the success rate and minimize the complications of CVC must be sought after. Material and Methods: This prospective, randomized study involved 60 children divided into two groups (n=30 each). Children less than 12 years were included and those with any neck swelling and/or undergoing univentricular repair surgery were excluded. Patients were induced with oxygen:sevoflurane, midazolam (0.1mg/kg IV), fentanyl (5-10 mcg/kg IV) and Inj. pancuronium (0.1 mg/kg IV). Internal jugular vein was cannulated using conventional anatomical landmark technique in group I and using USG in the group II. Time of the procedure was calculated once painting and draping was done until cannulation of an IJV. Left IJV and femoral vein cannulation was performed in case of inability to cannulate right IJV. Results: The percentage of successful first attempt cannulation was 36.66% in landmark group whereas in USG group it was 73.33%. Mean number of attempts in both the groups were 2.03 ± 1.13 vs 1.37 ± 0.72 in the landmark and USG group respectively.(P=0.008) Time required for procedure was more in the USG group (45.17± 25.61 vs 68.7± 48.98 seconds).[P=0.023] Carotid artery puncture occurred in 43.3% cases in landmark group as compared to 10% in the USG group.[P=0.004]. Conclusion: Ultrasound guidance reduces the number of needle passes needed to puncture the vein, increase the overall success rate of venous puncture and minimizes complications such as arterial puncture or pneumothorax.