The invention discloses a method for expanding and culturing peripheral blood T cells in vitro. In the method, a culture medium consists of a basic culture medium, fetal bovine serum, interleukin-2, interleukin-15, a human CD3 monoclonal antibody and a human CD28 monoclonal antibody. According to the method, T cells isolated from peripheral blood are activated and cultured in one cycle, a sufficient amount of cells for in vitro functional experiments can be obtained; after 7 days of expansion, number of the T cells can reach 40-50 times the initial amount; after 14-22 days of expansion, the number of the cells can reach 80-200 times the initial amount; furthermore, the CAR-T cells difficult to be expanded can be expanded to 60-80 times the initial amount on the 22nd day after in vitro infection, and the number is much greater than the initial isolation amount. According to the method, activation / expansion of the T cells and CAR-T cells is realized through stimulation of monoclonal antibodies and cytokines in the culture medium, no antigen-presenting cells or specific antigens or magnetic beads are needed, operation is simple, and culture cost is greatly reduced.