The present technology provides a method for diagnosing Alzheimer's disease, including the following steps: detecting a blood sample taken from a human subject suspected of having Alzheimer's disease,the biomarker level is selected from G72 protein level, SLC7A11 mRNA expression level,a combination of the two,compared with a preset standard, wherein if the detected biomarker level in the blood sample is higher than the preset standard, the Individual humans are thought to have Alzheimer's disease.