Purpose: Both type 2 diabetes mellitus (T2DM) and hypertension are regarded as lifethreatening diseases known to be risk factors for vascular diseases. They may be associated with the increased risk of cognitive impairment (CI), although there are conflicting data relating hypertension to the risk of CI. Therefore, this study aimed to explore the probable association between hypertension and CI in patients with T2DM. Patients and Methods: This cross-sectional study assessed the degree of CI of a total of 350 patients with T2DM using the Mini-Mental State Examination (MMSE). In clinical examinations, the mean of the first, second, and third measurements of systolic and diastolic blood pressure (SBP and DBP) was recorded. Results: The mean of subjects' MMSE scores was 25.48 ± 3.73. Additionally, the means of SBPSs and DBPs were found to be 118.50 ± 17.27 and 73.47 ± 10.25 mmHg, respectively. The Spearman correlation coefficient showed a mild, significant, negative correlation between MMSE scores and those of SBP (r = −0.199, p <0.001) and DBP (r = −0.233, p <0.001). Accordingly, a 1-unit increase in one's SBP would lead to a significant rise in mild CI (2.8%) in comparison with subjects who have normal CIs. However, it was shown that if one's DBP increased by 1 unit, the odds of mild CI occurring would increase significantly by 6.7% compared with those who have normal CIs. Conclusion: The present findings revealed that hypertension might be related to the development of CI in people with a diabetic condition, thus emphasizing the fact that the prevention and treatment of these highly prevalent diseases assume the utmost significance.