The invention belongs to the field of cytobiology, and discloses a culturing method for NKT cells. The culturing method for the NKT cells comprises the steps that mononuclear cells are inoculated into an X-VIVO15 serum-free culture medium, a hydroxypropyl methyl cellulose solution, 1L-2, 1L-15, 1L-21 and CD3 monoclonal antibodies are added, and then the NKT cells are cultured. According to the culturing method, the normal-temperature gelling effect of hydroxypropyl methyl cellulose is utilized, the hydroxypropyl methyl cellulose solution is added, a three-dimensional structure of a culture solution is built in the culturing initial stage of the NKT cells, therefore, the NKT cells proliferate in the three-dimensional space, the space is bigger, and the area of the contacted culture solution is sufficient. Experimental results show that by culturing the NKT cells through the culturing method for the NKT cells, the cells are good in state and high in proliferation speed and proliferation multiple, the NKT effect cells with the higher purity can be obtained, and the killing effect of the obtained NKT cells is obviously higher than that of NKT cells obtained through a conventional culturing method.