To our knowledge, this is the first report of case of high-grade endometrial stromal sarcoma metastasized to the stomach. Endometrial stromal sarcoma is very rare, accounting for 0.2% of female genital tract malignancies. High-grade endometrial stromal sarcoma demonstrates more frequent infiltration into the muscle layer of the uterus or metastasis to other organs, having a poorer prognosis than low grade disease. During its clinical course, endometrial stromal sarcoma may involve ovary, fallopian tube and pelvic cavity. Distant metastasis to lung, liver, bladder, breast, heart, brain and bones have been reported. However, to the best of our knowledge, high-grade endometrial stromal sarcoma presenting with gastric metastasis has never been reported. We now report a case of a 52-year-old woman with previously diagnosed lung metastasis having stomach metastasis from endometrial stromal sarcoma of the uterus.