The invention discloses a DC cell based on PAP antigen, a targeting immune cell population, a preparation method and applications thereof. The preparation method of DC cell comprises the following steps: subjecting mononuclear cells to first induced differentiation culture to obtain immature DC cells; transfecting the immature DC cells by PAP antigen mRNA to obtain transfected immature DC cells; subjecting the transfected immature DC cell to second induced differentiation culture to obtain mature DC cells; wherein the mononuclear cells are separated from peripheral blood mononuclear cells of a sample. Through the provided preparation method, DC cells can be obtained efficiently and safely. Moreover, the provided preparation method has the advantages of low cost and high efficiency, and can effectively solve the problem of cell toxicity. The DC cells can be applied to cell immunotherapy or used to trigger the lymph cells from the same patient to generate targeting immune cell population rich in CTL cells so as to achieve a better effect in tumor immunotherapy.