Introduction: Childhood overweight and obesity are global problemsthat are on the rise. Obesity in children appears to increase the risk ofsubsequent morbidity. The relevance of both hypertension and obesity, asimportant public health challenges, is increasing worldwide. Objective: Toidentify the interrelation between blood pressure and body mass index in a sample of Egyptian school children. Subjects &Method: A cross sectionalschool-based survey was performed on 816 students (6-18 years),425 weremales& 391 were females, from February through June 2008. Results: Theprevalence of hypertension was 10.5 %. The prevalence of obesity was1.5%. There were significant differences between normotensive andhypertensive children as regards BMI percentiles. The risk of developinghypertension in obese children was 1.7 higher than the risk in non obese(Odds ratio = 1.7). There was a significant positive correlation betweenBMI SDS and age. Conclusion: Age, weight and BMI are importantassociations for the risk of children to be hypertensive.