Abstract: By analysing the mark results of carcinoembrynic antigen in all kinds of uterous endometrium hyperplasia,we proved the significance of endometrium hyperplasia,in Precancerous Lesion.Method:We marked the carcino embryonic antigens of 102 endometrium hyperplasias by ABC immunohistockemical method. Conclusion:In order to Prevent the development of carcinoma,the differentiation of endometrium hyperplasia is important,the mark of carcinoembryonic antigen has significance on the differentiation of endometrium hyperplasia,and it supports that CAH is the precancerous Lesion,it also shows us that we must be careful to the SAH.