High blood pressure can cause damage to essential organs such as the heart, kidneys, brain, eyes and others. Regular physical exercise has been linked to improved health indicators including blood pressure and weight, while a lack of it has been linked to an increase in both blood pressure and the risk of cardiovascular disease in later life. This research was conducted with a cross-sectional design to know the relationship between physical activity and the blood pressure in orphanage children in Denpasar, Bali, Indonesia. All twelve orphanages in Denpasar were include in this study. Subjects were checked for blood pressure at the time of measurement. The instruments used to measure physical activity in the last seven days were the PAQ-C/A (Physical Activity Questionnaire-Children/Adolescent) questionnaire. Subjects who met the inclusion and exclusion criteria were included in the study. Subjects were recruited consecutively and met the study criteria of 177 people. Physical activity assessment with PAC showed that most subjects had moderate-high physical activity (87%), and only (13%) of subjects had low physical activity. Based on the prevalence risk (PR) value to assess the magnitude of the risk of hypertension in children with physical activity, it was found that low physical activity had a PR value of 12.275 (95% CI = 5.026 to 29.983). Low physical activity is a risk factor for increased blood pressure in children.