Background: Soy drink replacement in the diet might have beneficial effects on anthropometric and blood pres- sure values for overweight and obese subjects. Therefore, we are going to determine the effects of soy drink re- placements on the weight, waist circumference and blood pressure among overweight and obese female youths. Patients and Methods: This was a cross-over randomized clinical trial on 23 overweight and obese female sub- jects. All patients were on a weight reducing diet. There were two trial periods for six weeks (soy drink period and cow’s milk period) and a washout period for 3 weeks. In the soy drink period only one glass of soy drink (240 cc) was consumed instead of one glass of cow’s milk. Results: The mean age of the patients was 22±2 years. Mean of BMI was 28.1±0.5. Weight and waist circumference did not changed significantly after the soy drink period compared to the cow’s milk period. Systolic blood pressure reduced significantly following the soy drink period (mean percent change in soy drink period: -4.0±0.9 vs -1.7±0.5 in the cow’s milk period; p<0.05). Dia- stolic blood pressure also reduced in the soy drink period (-0.4±0.1 vs 0.4±0.1; p<0.05). Conclusion: Soy drink replacement could reduce both systolic and diastolic blood pressure among overweight and obese female youths. However, this replacement had no significant results on weight and waist circumference.