Background and Aim: This study aims to compare the topographical method and formula method for assessing the depth of central venous catheter (CVC) insertion in internal jugular vein (IJV) and subclavian vein (SCV) on both sides. Methods: Total of 496 patients were randomly assigned to eight groups; formula method right IJV, topographic method right IJV, formula left IJV, topographic left IJV, formula right SCV, topographic right SCV, formula left SCV, and topographic left SCV with 124 in each. The formula method involves mathematical calculations as described by Peres [3,14] and Kim et al. [2] to calculate the depth of catheter insertion. If the catheter tip was up to 1 cm above and below the carina as seen in post procedural chest x- ray it was considered to be in a satisfactory position. Results: The CVC's inserted via the IJV route on both the right and left sides were within the acceptable range when the depth of insertion was determined by the topographic method compared to the formula method {statistically significant for both right and left IJV (p< 0.001)}. The CVCs inserted via the subclavian route on both right and left sides by both topographic and formula methods were not in the acceptable range in majority of the patients and required repositioning. Conclusion: The topographic method was far superior then formula method in assessing the depth of CVC insertion in internal jugular vein on both right and left side whereas neither formula method nor topographic method was accurate in establishing optimal depth of CVC insertion by subclavian route in either right and left side.