BACKGROUND: This study aimed to investigate whether there are some differences between pediatric and adult patients with appendicitis. METHODS: We retrospectively reviewed the records of 279 pediatric and 275 adult patients with respect to demographics, past medical history, duration of symptoms, laboratory and radiological findings, operation notes, pathological reports, length of hospital stay and post-operative outcomes. RESULTS: No significant differences were found with respect to gender, rates of perforation and negative appendectomy, laboratory findings, and overall outcomes between children and adults. However, our study suggests that the diagnosis is more difficult in children, the most preferred radiologic diagnostic methods are abdominal ultrasound and plain X-ray in children vs. computed tomography in adults, air-fluid levels and right-sided scoliosis are more commonly detected on X-ray in children, appendiceal perforation is more common at both extreme of ages, the appendix is perforated earlier and length of hospital stay is longer in children, and misdiagnosis at first admission in children and advanced age in adults were the risk factors associated with the complications. CONCLUSION: The present study found some important differences between childhood and adulthood appendicitis. If these differences are considered when evaluating the patients, more desired outcomes can be achieved for both clinicians and patients. Keywords: Abdominal pain; adult; appendicitis; child.