The study was designed to assess retrospectively clinical pattern of insulinoma at a national referral center in the Kingdom of Saudi Arabia. All cases of insulinoma recorded at King Khalid University Hospital Riyadh between January 1987 and December 2006 were reviewed. During the 20-year period five patients were seen comprising three females (ages 38, 40, and 70 years) and two males (17 and 34 years). The duration of symptoms prior to diagnosis ranged between one and eight years. The commonest mode of presentation before diagnosis was inability to observe Ramadan fasting. Other notable symptoms included dizziness and loss of consciousness. All the five patients proceeded to operation. At surgery all were found to be benign tumors. Post-operatively, three of the patients developed pseudocyst, which resolved upon undergoing second surgery. Though clinical presentation of insulinoma in Saudi subjects is similar to those reported in the literature, our study revealed prominent symptoms occurring during yearly ramadan religious fast could be a useful information in history taking. Further studies on a larger population are needed to further characterize our findings.