Appendicitis is the most common diagnosis of acute abdominal pain that may require surgical treatment, and 8.6% for men and 6.9% for women are at risk for this illness over the course of their lives. During the past century, appendectomy was the standard treatment for acute appendicitis. However, laparoscopic appendectomy has been used as the first-line treatment choice for appendicitis since the introduction of laparoscopic surgery. In cases of perforation or abscess, interval appendectomy and percutaneous drainage are recommended. Treatment strategies have become more diverse. In recent years, in some European countries, non-surgical treatment has been used for simple appendicitis without complications, and nonoperative treatment of appendicitis has become increasingly common in adults and children. In this article, nonoperative treatment of appendicitis is introduced, and guidelines for the selection of antibiotics according to appendicitis classification are summarized.