Rhabdoid tumor has been considered to be a rare subtype of Wilm's tumor with Rhabdomyoma features. Since rhabdoid tumor that developed in the kidney was described for the first time in 1989, it has been reported in the gastrointestinal tract, although this is rare. The appropriate treatment is radical resection, and the effect of adjuvant chemotherapy has not yet been reported on. The outcome of extra-renal rhabdoid tumor is different from renal rhabdoid tumor and the former shows a poor prognosis. Among extra-renal rhabdoid tumors, undifferentiated gastric adenocarcinoma with rhabdoid features is very rare and its prognosis is poor. A 63 years old male patient underwent total gastrectomy for a tumor that developed in the greater curvature of the gastric body and this was diagnosed as undifferentiated gastric adenocarcinoma with rhabdoid features, according to the histopathology. We experienced an undifferentiated gastric adenocarcinoma with rhabdoid features that was diagnosed by immunohistochemical staining and we report here on this case.