The invention relates to a chimeric antigen receptor (CAR) containing a third signal receptor. The structure of the CAR is scFv(X)-(Y)CD3zeta-MN, wherein X comprises a tumor-targeting antibody or a ligand and receptor capable of being specifically combined with tumors, Y is an intracellular region of a costimulatory receptor, the costimulatory receptor is selected from ICOS, CD28, CD27, HVEM, LIGHT, CD40L, 4-1BB, OX40, DR3, GITR, CD30, TIM1, SLAM, CD2 and CD226, M is an intracellular region of a cytokine receptor of a gamma chain family, the cytokine receptor is selected from IL2Ra, IL2Rb, IL4Ra, IL7Ra, IL9Ra, IL15Ra and IL21Ra, and N is an IL2Rg intracellular region. The invention further relates to a CAR-T cell constructed from a recombinant expression vector of the CAR and a preparationmethod and application of the CAR-T cell. Through the CAR-T cell, the tumor killing ability and the amplification ability are significantly improved, the CAR-T cell contains the third signal receptor, the third signal receptor has the potential function of effect enhancement and only has the effect on the CAR-T cell, and the risk of causing immune side effects is reduced.