There is limited evidence on objectively measured physical activity from Africa. This study quantified physical activity by accelerometry in rural South African children at ages 7, 11, and 15 years. Total physical activity was generally high (mean accelerometer counts per minute ranged 485-1017 across the 3 groups), but moderate- to vigorous-intensity physical activity was low: <1% of the sample met international recommendations. A low intensity, high volume of physical activity is present in rural South African children and adolescents.