Introduction. Acute cholecystitis is one of the most common reasons of acute abdominal pain for older patients to present to the emergency department (ED). Presentation may differ from that of the younger patient and is often complicated by coexistent disease due to elderliness. In this study, we aimed to evaluate the clinical presentation of acute cholecystitis, with special focus on comparision between elderly and young patients. Materials and Methods. This study included 318 patients who were admitted to the emergency department with right upper quadrant pain during a period of determined 8 months. After retrospective data collection, patients were groupped in accordance with their age, <65 and ≥65 years. Those who had ultrasonographic signs such as wall thickening and fluid collection were diagnosed as acute cholecystitis. Results. The young group (Group I) consisted of 225 patients, 132 females and 93 males. In Group I, 39 patients were diagnosed as acute cholecystitis of whom 27 were females and 15 were males. The elderly group (Group II) consisted of 93 patients 48 females and 45 males. In Group II, 36 patients were diagnosed as acute cholecystitis of whom 15 were females and 21 were males. Regarding the diagnosis of acute cholecystitis, the female to male ratio is 2.25 in Group I and 0.71 in Group II (p=0.016). The average white blood cells counts of patients with acute cholecystitis in Group I and in Group II were 9907x109/L(±4.437) and 17083x109/L(±7485), respectively (p<0,001). Conclusions. Acute cholecystitis is a common diagnosis in elderly patients with right upper quadrant pain. It is more frequent in female in the early ages, but the gender difference tends to change with age. Elderly patients demonstrate a higher level of white blood cells when compared to young patients in acute cholecystitis. Clinicians must maintain a degree of awareness in the evaluation of geriatric patients with right upper quadrant abdominal pain.