BACKGROUND:–Cholecystectomy as a factor causing change in common bile duct diameter has been the topic of debate for most surgeons. The aim of this study is to observe the size of Common bile duct (CBD) in patients before and after cholecystectomy. METHODS AND MATERIALS:– We prospectively analyzed 60 patients who underwent cholecystectomy in RIMS, Ranchi, in Dept. of Surgery from 01/10/2017 to 01/04/2019. Pre operative CBD calibre measurements by ultrasound were compared with measurements taken at 1–month, 6–months and 12–months from the day of surgery. Thus we looked for any compensatory dilatation of CBD if present. RESULTS:– In only 3 out of 60 patients significant dilatation of CBD was seen. Although a trend towards minor dilatation was observed in the rest. Mean CBD preoperatively 4mm. Mean CBD at 1–month after surgery 4.7 mm, mean CBD at 6–months 5.8 mm, mean CBD at 12–months 6.0mm. CONCLUSION:– CBD dilatation within 10mm in gall bladder resected patients can be regarded as normal physiological change.