The invention provides a double-antigen epitope fusion gene recombinant lentiviral vector, an antigen presenting cell, a CTL (Cytotoxic T lymphocyte) cell as well as construction methods of the antigen presenting cell and the CTL cell and application of the CTL cell, and belongs to the technical field of tumor drugs. The double-antigen epitope fusion gene recombinant lentiviral vector comprises afusion gene formed by an MAGE-A3 gene and a KRAS mutant gene. After the recombinant viral vector is packaged into a recombinant lentivirus, a double-antigen encoding gene is introduced into a genome of a DC (Dendritic cell) cell by taking the recombinant lentivirus as a mediated vector to obtain the antigen presenting cell simultaneously presenting MAGE-A3 and KRAS mutant double antigens. A T cellis induced by the antigen presenting cell through utilizing a DC-CTL technology to obtain the specific CTL cell with targeted MAGE-A3 and KRAS mutation. Based on the relatively strong double-antigenkilling effect of the CTL cell, the CTL cell is used for preparing drugs for treating cancer or tumors.