The Sister Mary Joseph's nodule is a periumbilical metastatic tumor originating from advanced metastatic intra-abdominal and intrapelvic malignancies. It is an inconspicuous and uncommon clinical sign, which not only shows the presence of visceral malignancy but also reveals the poor prognosis of these malignancies. The majority of cases originate from gastrointestinal or ovarian cancer. We present a case of an 80-year-old woman with an umbilical nodule, which was the sole presenting symptom of advanced signet ring cell carcinoma of the stomach with generalized peritoneal carcinomatosis. There are very few cases of gastric signet ring cell adenocarcinoma presenting as a SMJN, a fact rather striking as signet ring cell gastric carcinoma has an increased frequency of peritoneal dissemination and carcinomatosis of the peritoneum.