Chimeric antigen receptor (CAR) T cells have shown decent therapeutic efficacy in treating hematologic cancers; however, their effectiveness has been limited so far in the case of solid tumors. This inability of CAR T cells to overcome solid tumors is partly due to the physical barriers, tumor cells’ antigen heterogeneity, immunosuppressive tumor microenvironment (TME), and the scarcity of nutrient supplies such as amino acids and carbohydrates in the TME, which cause exhaustion and reduced activity of the adoptively transferred CAR T cells. CAR T cells need metabolic support for successful proliferation and maintaining their effector and memory functions. Given that the therapeutic outcome of CAR T cell therapy in patients is highly dependent on their activity and longevity, therefore, reprogramming their metabolism could be considered a great option to improve their effectiveness in fighting tumor cells. Metabolic enzymes, signaling pathways, mitochondria, and the costimulatory domains are among the factors that regulate the metabolic program of CAR T cells. In this chapter, we will first discuss the metabolic signatures of T cells and how tumor cells’ metabolism could affect T cells, and then the potential ways to manipulate CAR T cells metabolism will be reviewed.