β-Human chorionic gonadotropin (β-HCG) is an embryonic protein secreted by the syncytiotrophoblast of the placenta. The determination of the plasma β-HCG level is routinely used for the diagnosis and the follow-up of germ cell tumors. Some adenocarcinomas have been described as being rarely associated with β-HCG hypersecretion. We report a case of gastric signet-ring cell carcinoma with β-HCG hypersecretion and propose hypotheses to explain the pathogenesis of such hypersecretion.