Background: CDX2 is an intestinal-specific gene and activated CDX2, ensures inhibition of cell proliferation, and differentiation of intestinal epithelial cells. Immunohistochemically CDX2 expression is common in neoplastic and non-neoplastic cells in the gastrointestinal system. CDX2 is used especially in differential diagnosis of metastatic tumors in pathology practice. Recently it is reported that CDX2 expression may be found outside of the gastrointestinal system. Aims: In the present study, the authors aimed to research the CDX2 expression in endometrioid adenocarcinoma in endometrium and attempt to determine the relationship with grade and stage. Materials and Methods: The study included 92 cases with endometrial endometrioid adenocarcinoma. Sections prepared in paraffin blocks were researched immunohistochemically for CDX2 expression. Results: Expression was detected 31/92 of the cases. In 13% of cases (12/92), positivity was detected in the glandular area of the tumor tissue while in 20% of cases (19/92) expression was identified in the morular metaplasia area. It was noted that in two cases there was strong expression in the glandular area. Conclusions: CDX2 expression may be observed in endometrial endometrioid adenocarcinoma. This situation does not imply intestinal metaplasia. Especially as histopathological evaluation of metastatic tumors may cause misdiagnosis, in endometrioid adenocarcinoma in non-morular tumoral tissue, it should be remembered that, though rare, intense CDX2 expression may be found.