A barolith consists of inspissated barium associated with feces and is seen, rarely, after barium studies for imaging the gastrointestinal system. The barium used in such studies can enter the appendiceal lumen and, rarely, cause appendicitis by obliterating or narrowing the lumen of the appendix. The appendix fills with barium and the entire appendix is visualized in 80-90% of barium swallow or enema studies, and this is accepted as a reliable sign of a non-diseased appendix Post-examination retention of barium in the appendix is very common (90 similar to 95%), and 10% of the patients retain barium in the appendix beyond 72 hours. If the barium is retained for more than two months, complicated appendicitis can result. We present a 46-year-old male who was diagnosed with acute appendicitis due to a barolith and required an appendectomy three months after a double-contrast barium enema study. After barium studies, patients should be informed regarding retention of barium in the appendix and the possibility that it can cause acute appendicitis. Thus, if abdominal pain develops, the patient can be referred quickly to a medical center for the appropriate treatment and the complications of acute appendicitis can be prevented with early intervention.