The invention relates to a photonic crystal optical fiber for generating a column vector optical field. A plurality of fiber cores are introduced into the photonic crystal optical fiber through defect air holes; optical power is coupled and distributed by the optical cores; light entering the optical fiber meets a total internal reflection condition and is limited in the fiber core to be transmitted; each fiber core has a pair of cross-polarized base modes to form four types of discrete type vector optical field modes. The photonic crystal optical fiber has the beneficial effects that large air hole and defect air hole structures are designed in the multi-core photonic crystal optical fiber and a mode high-reflection difference and defect mode is introduced; influences on the vector mode by polarization mode color dispersion and polarization mode coupling are eliminated, and the high-quality vector optical field is generated. The end face of the optical fiber is regular and can be coupled with a passive or active optical device and laser emission of the vector optical field is realized. A simple and easy method is provided for generating the vector optical field and long-distance transmission of the vector optical field can be realized.