Endometrial osseous metaplasia is a rare condition. The etiology and pathogenesis remain controversial. In most cases, the development of this condition is observed to be related to the history of abortion, either spontaneous or therapeutic and also, frequently associated with menstrual irregularity and endometritis. Patients usually present with secondary amenorrhea, irregular menstruation, pain, and dysmenorrhea. The authors recently experienced a case of endometrial osseous metaplasia of a referred endometrial cancer patient who had no history of abortion at all. We report this case with a brief review of the literature.