Abstract: Tie2 expressing monocytes/macrophages (TEMs) are a subtype of monocytes or macrophages which expressing tyrosine kinase receptor Tie2. They can exist in peripheral blood and tissues of both human and mouse. TEMs can participate in the formation of tumor microenvironment by accelerating tumor angiogenesis, lymphangiogenesis and immunosuppression. At present, TEMs have been found to have potential diagnostic and prognostic guiding significance for a variety of tumors, and they are expected to provide new directions and strategies for tumor therapy. This paper reviews the research progress of TEMs in tumor.