Chronic appendicitis is caused by inflammation of the appendix for several weeks, and the patients have symptoms such as mild nausea, abdominal pain, and tenderness. Diagnosis of chronic appendicitis is difficult because the symptoms are mild and vague compared to the acute appendicitis. In radiologic examination, appendicitis usually appears dilatation with diffuse wall thickening of appendix. Surgical treatment of the appendix (appendectomy) could be recommended against complications such as acute appendicitis or perforation. We have incidentally experienced an unusual case of chronic appendicitis without symptoms, and report its radiologic findings and clinical manifestations. Key words: Appendix; Appendicitis; Asymptomatic diseases; Chronic disease; Appendectomy