Background. Arterial hypertension is a multicausal chronic disease often accompanied by obesity. The aim of this investigation was to examine the effect of diet therapy in the treatment of obese hypertensives with and without antihypertensive therapy. Methods. The investigation was conducted at the Department of Nutrition on a sample of 110 obese hypertensive patients on diet therapy. Subjects were divided into two groups: the group on diet therapy with antihypertensive drugs E1 (n=78), and the group on diet therapy without pharmacotherapy E2 (n=32). Nourishment state i.e., obesity level was assessed by body mass index (BMI). All the patients belonged to the obese group - BMI > 30 kg/m2. Besides blood pressure values, the following parameters were monitored: serum cholesterol, trygliceride levels and BMI. Results. The obtained results in the group with diet therapy combined with antihypertensive therapy showed highly significant decrease of anthropometrical parameters: body weight (99.14 kg vs. 90.16 kg) (p<0.001) and BMI (37.32 vs. 34.09) (p<0.001); percent body fat (41.97 vs. 38.78) (p<0.001); systolic (154.81 vs. 141.91) (p<0,001), and diastolic pressures (95.42 vs. 87.36) (p<0,001); cholesterol (6.39 vs. 5.99) (p<0,002), and triglycerides concentration (2.69 vs. 2.21) (p<0.019). In the group on single diet therapy, highly significant decrease of body mass (99.33 vs. 90.18) (p<0.001), BMI (34,79 vs. 31.58) (p<0.001), percent body fat (39.27 vs. 36.70) (p<0.001), systolic (148.44 vs. 132.74) (p<0.001), and diastolic pressures (93.97 vs. 82.90) (p<0.001), was achieved, while the differences between initial and final cholesterol and triglyceride concentrations although observed, were not statistically significant. Conclusion. The obtained results implicated that diet therapy significantly helped the normoregulation of both systolic and diastolic blood pressure. Considering this, during physicians’ routine practice in the treatment of hypertension attention should be paid on the reduction of the corresponding level of obesity.