Abstract Background: Laparoscopic cholecystectomy has been the gold standard in the treatment of gallstone disease, and most of cholecystectomies are performed this way today. However, it is recognized that 3-33% of patients with symptomatic gallstones might harbor common bile duct (CBD) stones. Aim of Study: To evaluate the sensitivity and accuracy of GGT in the diagnosis of silent common bile duct stones in patients diagnosed with gall stones and scheduled for chole-cystectomy. Patients and Methods: We established this prospective observational study on 30 patients who are diagnosed with gall bladder stones with normal or elevated gamma glutamyl-transferase referred to General Surgery Department, Ain Shams University and General Surgery Department, El Sahel Teaching Hospital. Results: It was found that there common bile duct stones was significantly higher in cases with high GGT compared to cases with normal GGT (p=0.033). It was found that multiple common bile duct stones was significantly higher in cases with high GGT compared to cases with normal GGT (p=<0.001). In addition, the decision of doing ERCP before laparoscopy was significantly higher in cases with high GGT compared to cases with normal GGT (p=<0.001). Conclusion: Abnormally elevated serum GGT level may be a potentially useful marker for the early prediction of asymptomatic choledocholithiasis secondary to cholecysto-lithiasis.