Current technological advances in clinical and research fields have enabled people to have a deeper and comprehensive understanding of Alzheimer's disease (AD). β -Amyloid (Aβ) is the core biomarker of AD. Aβ-PET can objectively detect the abnormal Aβ deposition and distribution in the brain, and can be widely used in the early accurate diagnosis and therapeutic evaluation of AD. This article elaborates on the detection methods and advantages and disadvantages of AD biomarkers, with a focus on the application and value of Aβ-PET in the diagnosis and treatment of AD.