Abstract: A fusion protein, an amino acid sequence thereof, a coding nucleotide sequence thereof, a preparation method thereof and a use thereof are in the technical field of agricultural biotechnology. The fusion protein contains or consists of at least three, four, five, six, seven, or eight same and/or different PAMP (Pathogen-Associated Molecular Pattern) polypeptides. Optionally, there is at least one linker or no linker between two adjacent PAMP polypeptides. A plurality of PAMP polypeptides are assembled into the fusion protein having multiple immune epitopes. The fusion protein may induce defense immune responses of plants, weaken infestation ability of pathogenic microorganisms and substantially improve the disease resistance of plants. The method for preparing the fusion protein combines technologies of PTI (PAMP-Triggered Immunity) mechanism and gene engineering to obtain the fusion protein having multiple immune epitopes can be used in preparation of plant immune PAMP polypeptides.