Abstract Background: Blood viscosity level increases in hyperten-sive patients. Objective of this study was to determine the effect of aerobic training on blood viscosity in hypertensive women. Aim of Study: To investigate effect of aerobic training on blood viscosity in hypertensive women. Material and Methods: Thirty obese diabetic women participated in this study chosen from Al-Bagour public hospital in 2018. The patients were assigned into two equal groups. Each group included 15 patients. The patients in both groups were matched in age ranged from (50-65 years old) and body mass index ranged from (25 to 29.9Kg/m2), with mild to moderate hypertension and had high blood viscosity >4.5 relative to water. All patientsreceived medications ac-cording to physician prescription, Group A received a program of aerobic training using treadmill 3 days/week for 8 weeks with intensity 60-80% MHR started with 20 minutes and increased by 5 minutes every two weeks till reaching 40 minutes at 8th week. Warm up phase 5-10 minutes, cool down phase 5-10 minutes in form of walking on treadmill at low speed.while group B acted as control group. Results: The data revealed a statistically decrease in blood viscosity level in group A than in group B after treatment (p<0.05). The percentage of improvement in group A was 20% while it was 7.2% in group B. Conclusion: Aerobic training had valuable effect on blood viscosity level in women with hypertension.