This study was performed on 40 adult patients having calcular biliary obstruction and was referred to the Gastrointestinal Endoscopy and Liver Units of Kasr Al Aini and Theodore Bilharzia Research Institute Hospital for ERCP. Twenty -two were females and 18 were males. Their age ranged from 22 to 63 years. Initial evaluation included history taking, clinical evaluation, laboratory investigations and measurement of amylase level in serum. After ERCP patients were monitored for at least six hours and measurement of serum amylase was done again. Out of 40 patients enrolled in the study 6 patients (15%) developed pancreatitis. It was self-limiting in all of them. Hyperamylasemia occurred in 60% of the patients. Age, sex, bilirubin level and precut sphincterotomy were not risk factors for pancreatitis, while number of trials of cannulation, pancreatic duct cannulation, size of extracted stones and degree of difficulty of extraction were significantly related to the risk of pancreatitis.