A case of a ferromagnetic foreign body in a medically compromised patient was reported. The patient was a 45-year-old male who consulted our department complaining of a foreign body accidentally impacted in the right cheek. X-ray examination revealed a foreign body at the lateral aspect of the right mandibular ramus. The removal of the foreign body was scheduled, but the patient did not return for the procedure. After 8 years he revisited our department for the removal of the foreign body, because it had been found to be ferromagnetic and a barrier to MRI examination. X-ray examination confirmed the foreign body was located at the same site as 8 years prior. Although the patient was suffering from liver cirrhosis with thrombocytopenia and leukopenia, the foreign body was successfully removed under general anesthesia. The foreign body was 12 × 5 × 1 mm, weighed 0.48 g, and was ferromagnetic. The patient’s postoperative course was uneventful. X-ray examination confirmed the removal of the foreign body. Since the surgery, the patient has been in generally stable condition with no complications. This case was a rare example of a foreign body that needed to be removed for medical examination.