Abstract: Objective:To observe the clinicopathological features,immunohistochemical type and differential diagnosis of uterine fibromatosis.Methods:One case of uterine fibromatosis was studied with histopathology,immunohistochemistry examination and the related literatures were reviewed.Results:Grossly,the mass was nodulated and indistinct margin,with a white-grey cut surface.Microscopy revealed that the neoplasm was composed of spindle cells and collagen fibers,arrayed bunchy and striation,extended to the surrounding tissue.Immunohistochemical findings showed that the tumor cells were positive for vimentin,partly positive for SMA,but negative for Desmin,H-caldesnen and Calponin.Conclusions:The diagnosis of uterine fibromatosis mainly relies on pathological examination.Morphologically,it should be differentiated from other spindle cell lesions in the uterus,such as hysteromyoma,adenomyosis,fibrosarcoma,perivascular epithelioid cell tumor,leiomyosarcoma and endometrial stromal sarcoma.