The ingestion of a foreign body that penetrates the gastric wall and migrates to the liver, where it causes an abscess is uncommon. A case of an ingested rosemary twig perforating the gastric antrum, then migrating to the liver, complicated by hepatic abscess and Staphylococcus aureus sepsis is reported. A 59-year-old man without a history of foreign body ingestion was admitted to our hospital because of sepsis and epigastralgia, which had progressively worsened. No foreign body was identified at preoperative imaging, but a rosemary twig was discovered during laparotomy. The liver abscess and sepsis were controlled successfully with surgery and antibiotics. This unusual condition should be kept in mind when dealing with cases of hepatic abscess, or even sepsis of unknown origin. Despite the improvement of non-surgical techniques such as percutaneous drainage and interventional endoscopy, surgery still remains important in the treatment of hepatic abscess caused by an ingested foreign body.