Objective To study the expression characteristics and clinical significance of miR-26b and miR-30e in serum of patients with Alzheimer disease （AD）. Methods A total of 200 patients with senile dementia admitted to our hospital from June 2015 to September 2017 were selected for the study. Among them， 100 patients with AD were assigned as AD group， the other 100 patients with mild cognitive impairment （MCI） were assigned as MCI group. Another 100 patients who took health examination in our hospital during the same period were assigned as NC group. Real-time fluorescence quantitative polymerase chain reaction （qRT-PCR） was used to detect the expression levels of miR-26b and miR-30e in serum of each group. The general clinical data and the contents of triglyceride （TG）， total cholesterol （TC）， low density lipoprotein cholesterol （LDL-C）， high density lipoprotein cholesterol （HDL-C）， homocysteine （Hcy） and adiponectin （ANP） were compared among the three groups. Pearson correlation analysis was used to analyze the correlations between serum miR-26b， miR-30e and biochemical parameters in AD patients. The risk factors of AD were analyzed by binary logistic regression. Results Compared with NC group， the levels of serum Hcy and LDL-C in AD group and MCI group increased significantly， while the level of ANP decreased significantly （P ＜ 0.05）. The levels of serum miR-26b in AD group and MCI group were 0.51 （0.15，0.86） and 0.79 （0.21，1.14） respectively， which were significantly lower than that in NC group 1.06 （0.42， 1.32） （P＜ 0.05）. The levels of serum miR-26b in AD group were significantly lower than that of MCI group （P＜0.05）. The level of serum miR-30e in AD and MCI groups were 1.27 （0.53，1.72） and 1.02 （0.35，1.65）， which were significantly lower than those in NC group 0.86 （0.43，1.32） （P＜ 0.05）. The serum level of miR-30e in AD group was significantly higher than that in MCI group （P＜ 0.05）. The expression level of miR-26b was positively correlated with ANP （r=0.626，P＜ 0.05）， and negatively correlated with LDL-C and Hcy （r=-0.517，-0.523，P＜ 0.05）. The expression level of miR-30e was positively correlated with LDL-C and Hcy values （r=0.536，0.644，P ＜ 0.05）， while negatively correlated with ANP values and the expression level of miR-26b （r=-0.732，-0.563，P ＜ 0.05）. Logistic regression analysis showed that Hcy， LDL-C， miR- 26b and miR-30e were independent risk factors for AD （P ＜ 0.05）. And ANP was protective factor for AD （P ＜ 0.05）. Conclusions The expression of miR-26b in serum of AD patients is significantly down-regulated， the expression of miR-30e is significantly up-regulated. Both miR-26b and miR-30e are related to the occurrence and development of AD.