It was found that the sensitivity, specificity and the area under the curve of plasma Aβ40, Aβ42, and P-Tau were all greater than cortical thickness indexes in the AD-NC, AD-aMCI, and aMCI-NC groups, certifying that plasma Aβ40, Aβ42, and P-Tau had good sensitivity and specificity for the early recognition of AD, which was in agreement with the studies of Schindler et al. (2019), Shen et al. (2020), and Zou et al. (2020). This evidence concerns the gene MAPT and Alzheimer disease.