Due to the primary disease or chemotherapy-induced neutropenia, patients with acute myeloid leukemia (AML) become a high-risk population for infections. This article discusses the effects of AML cells and chemotherapeutic drugs on the immune function of CD4 ⁺ and CD8 ⁺ T lymphocytes, as well as the role of their quantitative changes in identifying the risk of infection during the post-chemotherapy bone marrow suppression period in AML. It summarizes the immune function of CD4 ⁺ and CD8 ⁺ T lymphocytes in the diagnosis of infections and pathogen differentiation during the post-chemotherapy bone marrow suppression period in AML.