The amyloid cascade hypothesis is widely accepted by researchers as the mechanism of Alzheimer's disease. Active immunization to eliminate Aβ depositions has been used in preclinical and clinical studies. Aβ3-10-KLH is a vaccine of the Aβ3-10 peptide combined with keyhole limpet hemocyanin (KLH). We immunized 2.5-month-old Tg-APPswe/PSEN1dE9 mice with Aβ3-10-KLH peptide and Aβ1-42 peptide to eliminate Aβ deposits in the brains of these transgenic mice. The results of immunohistochemical staining and transmission electron microscopy detection indicated that our new vaccine was more advantageous in protecting synaptic function and structure than the Aβ1-42 peptide. Aβ3-10-KLH peptide is an effective vaccine in the treatment of Alzheimer's disease.