We report a case of adenomyoma of endocervical type that occurred in a 28-year-old-woman. The patient presented with a mass protruding into vagina which was treated by polypectomy. Histologically, tumor was composed of a mixture of proliferating glands of endocervical type and fascicles of smooth muscle cells. There were no architectural abnormalities. Both the epithelium and smooth muscle were uniformly bland. No mitotic activity was observed in the epithelial and stromal component. Polypectomized specimen was diagnosed as adenomyoma of endocervical type. This tumor type should be added to the list of a differential diagnosis of uterine endocervical tumor.