Solitary carcinomatous metastases to the spleen are rare, and the presence of solitary splenic metastasis of hepatoid adenocarcinomas (HAC) has not yet been reported. We herein present the case of a 54-year-old male patient who developed a metastatic tumor to the spleen with enhanced levels of serum α-fetoprotein and carcinoembryonic antigen (CEA). The patient underwent a gastrectomy due to adenocarcinoma of the stomach 5 years previously. The tumor was diagnosed on the grounds of histopathology and immunohistochemical staining after splenectomy. The pathology slides showed both adenocarcinoma and hepatoid structures. α-Fetoprotein antibody staining was positive in the tumor, suggesting hepatoid characteristics. After the operation, the patient recovered well and had no signs of recurrence at a follow-up examination after 9 months. Together with this case, several aspects of the disease are discussed after a review of the current literature.