OBJECTIVE The accuracy of a surgeon's judgement still remains to be controversial in the diagnosis of acute appendicitis, which is a diagnosis usually based on laboratory data and imaging tests. MATERIAL AND METHODS Patients with a possible diagnosis of acute appendicitis were reviewed retrospectively with regard to demographic variables, laboratory and imaging results, and treatment modalities. RESULTS There were 128 patients with a mean age of 31.2±14 years. The mean white blood cell count and the proportion of polymorphonuclear leukocytes were 11403±4669/mm(3) and 75±11%, respectively. Appendectomy was performed on 66 (51.6%) patients. Conservative management was applied to 62 (48.4%) patients. Statistical analysis showed that patients with appendicitis have a higher white blood cell count (p=0.015) and a higher proportion of polymorphonuclear leukocytes (p=0.023). Sensitivity, specificity and accuracy rates were 84.6%, 63.7% and 74.3% for ultrasound and 100%, 86.7% and 92.2% for computed tomography, respectively. CONCLUSION Diagnosis based on patients' laboratory and imaging data, in combination with, the surgeon's judgement appears to yield the best outcomes in patients with suspicion of acute appendicitis.