Immunotherapy can mobilize the natural antitumor ability to achieve targeted elimination of tumor cells, with minimal toxicity to normal cells. Adoptive cell therapy has evolved over several generations, from the earliest lymphokine-activated killer cells (first generation) and cytokine-induced killer cells (second generation), to tumorinfiltrating lymphocytes (third generation), antigen-specific cytotoxic T lymphocytes (fourth generation), and chimeric antigen receptor (CAR; fifth generation) T cells. In recent years, CAR T-cell therapy has

Leukemia and lymphoma—the most common hematological malignant diseases—are often accompanied by complications such as drug resistance, refractory diseases and relapse. Amino acids (AAs) are important energy sources for malignant cells. Tumor‐mediated AA metabolism is associated with the immunosuppressive properties of the tumor microenvironment, thereby assisting malignant cells to evade immune surveillance. Targeting abnormal AA metabolism in the tumor microenvironment may be an effective therapeutic approach to address the therapeutic challenges of leukemia and lymphoma. Here, we review the effects of glutamine, arginine and tryptophan metabolism on tumorigenesis and immunomodulation, and define the differences between tumor cells and immune effector cells. We also comment on treatments targeting these AA metabolism pathways in lymphoma and leukemia and discuss how these treatments have profound adverse effects on tumor cells, but leave the immune cells unaffected or mildly affected.