Abstract: Objective To investigate the pathological features and immunophenotype which were related to recurrence of the uterine adenosarcoma in adolescence.Methods The primary and recurrent uterine adenosarcoma in an adolescence were observed by morphology and immunohistochemistry.The related literatures were reviewed.Results The primary and recurrent tumor both were composed of an admixture of benign-appearing glands and a sarcomatous stroma.The sarcomatous stroma in primary tumor constructed by endometrial stromal sarcoma with sarcomatous overgrowth and had myometrial invasion.Recurrent tumor possessed more sarcomatous area and had chondrosarcoma compared with primary tumor.Immunohistochemically, the sarcomatous stroma cells in primary tumor:p53(+), Ki-67(＞70%, +), ER(-), PR(-).Conclusion The pathological features and immunophenotype related to recurrence may be sarcomatous overgrowth, myometrial invasion, immunohistochemical stain positive for p53, strongly positive for Ki-67 and negative for ER, PR.