The invention relates to a double-target CD19 and CD22 chimeric antigen receptor and application thereof, in particular to a polynucleotide sequence which is selected from (1) a coding sequence comprising anti-CD22 and anti-CD19 single-chain antibodies which are connected sequentially, a coding sequence of a human CD8 hinge region, a coding sequence of human CD8 transmembrane region, a coding sequence of a human 41BB intracellular region, a coding sequence of a human CD3 zeta intracellular region and a polynucleotide sequence of a coding sequence of a fragment, comprising an extracellular domain III and a extracellular domain IV, of an optional EGFR; and (2) a complementary sequence of the (1) polynucleotide sequence. The invention further provides a relevant fusion protein, a carrier comprising the coding sequence and application of the fusion protein, the coding sequence and the carrier. The prepared CD19-CD22-BBzCAR-T cell has a strong killing function to the specific tumor cell, CD107a expression and IFN gamma secretion are high, and the killing efficiency to the target cell can reach about 80% under the situation that the effector-target ratio is 10:1.