Provided in the present invention are a β-sheet breaker peptide used for preventing and/or treating Alzheimers disease, and the use thereof for preventing and/or treating Alzheimers disease. The amino acid sequence of the β-sheet breaker peptide is His-Lys-Gln-Leu-Pro-Phe-Tyr-Glu-Glu-Asp (SEQ ID NO:1). The polypeptide can specially bind to a β-amyloid protein monomer (Aβ1-42), and prevent the formation of β-sheet, thereby inhibiting Aβ peptide aggregation, reducing the formation of Aβ soluble oligomer, Aβ fiber and senile plaques in the brain, and accelerating the degradation and removal of Aβ peptide.
