Acute abdominal pain leads to many differential diagnoses, all of which make it difficult to put them together during a clinical examination. One of rare causes of abdominal pain is Ascaris worm infection that can have various manifestations. This study reports a patient with acute abdominal pain with intestinal ascariasis. A 30-year-old male patient with Right Lower Quadrant pain (RLQ) of the abdomen, nausea, and vomiting referred to the Emergency Department (ED). An incidental discovery of Ascaris worm with 25 cm length occurred after Appendectomy. Although the clinical signs of ascariasis are nonspecific, a complete history and careful examination, and especially attention to epidemiological considerations, are very effective in diagnosing the disease. It is also recommended that surgeons consider such etiologies in the mind, to search further in the intestinal tract to find the cause.