Background: Hypertension is one of the prevalent and dangerous complications of diabetes mellitus. As it is difficult to control hypertension, the necessity of using new techniques such as non-pharmaceutical methods and complementary therapy increased. This study aimed to determine the effect of aerobic exercise on the blood pressure of patients with type 2 diabetes. Methods: This study was a quasi-experimental randomized trial conducted on 67 volunteered patients with type 2 diabetes. The participants were randomly assigned to aerobic exercise (n=33) and control (n=34) groups. The exercise group walked 30 minutes, 3 days a week for 8 consecutive weeks. Systolic and diastolic blood pressure of the samples were measured before and after the intervention. The data were analyzed by descriptive statistics, the Kolmogorov-Smirnov test, paired t test, Independent t test, and Chi-square test using SPSS (v. 16). P value less than 0.05 was considered significant.  Results: The difference between the systolic and diastolic blood pressure of the groups before the intervention was not significant (P>0.05). After the intervention, there was no significant difference in terms of systolic and diastolic blood pressure of the exercise group compared with the baseline (P>0.05). No significant difference was determined between groups in terms of systolic and diastolic blood pressure after the intervention (P>0.05). Conclusion: According to the findings, 8 weeks of aerobic exercise (walking) did not reduce systolic and diastolic blood pressure in patients with type 2 diabetes.