Objective To investigate the effect of dyslipidemia on mild cognitive impairment (MCI) in the elderly with type 2 diabetes mellitus (T2DM). Methods From January 2018 to January 2019, a total of 378 elderly T2DM patients were selected from our department. According to their cognitive function, they were divided into two groups:normal group (n=302) and MCI group (n=76). Mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA) were employed for cognitive screening, and baseline data and clinical parameters were collected. SPSS statistics 17.0 was used for data processing. Multivariate logistic regression was used to analyze the risk factors for MCI. Results The analysis with stratification by median age (70 years) showed that, in the group over 70 years old (n=180; 52 with MCI), low-density lipoprotein cholesterol (LDL-C) (OR=3.01,5%CI 1.37-6.96, P=0.006) and total cholesterol (TC) (OR=1.75,5%CI 1.16-2.64, P=0.008) were the risk factors for MCI in the elderly T2DM patients. When the patients were further stratified according the level of blood lipid, the results showed that TC≥5.2mmol/L increased the risk of MCI to 2.59 folds (P=0.019) and LDL-C≥ 3.4mmol/L to 3.24 folds (P=0.001) in T2DM patients. Conclusion The occurrence of MCI in the elderly T2DM patients may be closely associated with the increase of TC and LDL-C levels.