Introduction. The diagnosis of acute appendicitis (AA) is difficult and remains one of the most challenging diagnostic issues in surgery in all age groups. Elderly patients have poor response, their symptoms and pathological changes are often inconsistent with abdominal pain, whereas the differential diagnoses are wide and difficult due to many other possible diseases, which may mimic AA. Aim of the study. To evaluate the informative value of conventional clinical signs on presentation, as well as the role of imaging methods in diagnosis and decision for surgery in the elderly patients with AA. Materials and methods. A total of 78 patients treated in the Department of General Surgery with histologically confirmed AA were included in the retrospective analysis (Jan-Oct 2017). Women were 52 (66.6%) and men - 26 (33.3%). Among study group 68 (87.2%) patients were under the age of 60 years, and 10 (12.8%) were over 60 years. The information regarding patient’s demographic data, initial clinical presentation and assessment, laboratory tests, radiological studies with focus on abdominal ultrasonography (US) and computed tomography (CT) scan was collected. Results. The duration of the preoperative hospitalization over 24 hours was considerably higher in the elder group: 30% vs. 8.8% in the younger group, but this finding was not statistically significant (p>0.05). Only in two (20%) cases the diagnosis of AA in the elderly patients was based on clinical data only versus 44 (64.7%) - in younger population. In the remaining 8 elderly patients additional instrumental methods of diagnosis (abdominal US or CT scan) were required to confirm the appendicitis, to exclude alternative diagnoses of acute abdomen, and to make up the decision for surgical treatment (80% vs. 35.3% in the younger patients, p<0.05). Conclusions. The classic symptoms of AA are not indicative in elderly patients and cannot serve as a basis for reliable diagnosis, which requires more frequent use of imaging modalities, including USG and CT, and the decision for surgery is often taken on the basis of instrumental data.