Follicular helper T cells (Tfh) and follicular regulatory T cells (Tfr) are newly discovered CD⁴⁺ T cell subsets with opposite effects. In the process of germinal center and humoral immunity, Tfh cells assist in the production of antibodies, while Tfr cells inhibit the function of Tfh cells and B cells. The immune balance of Tfh/Tfr cells plays an important role in the formation of germinal center, the proliferation and differentiation of B cells and the production of antibodies. Tfh/Tfr cell balance is closely related to autoimmune diseases, solid tumors and some hematological diseases, but its role in malignant hematological tumors is not clear. This paper reviews the latest research progress of Tfh/Tfr cell immune balance in malignant hematological tumors, which points out a new direction for the pathogenesis and immunotherapy of malignant hematological tumors.