With the rise of type 2 diabetes in youth, it is critical to investigate factors such as physical activity (PA) and time spent sedentary that may be contributing to this public health problem. This article describes PA and sedentary time in a large cohort of youth with type 2 diabetes and compares these levels with other large-scale investigations. The Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) trial is a study in 699 youth, recruited from 15 US clinical centers, aged 10 to 17 years with <2 years of type 2 diabetes and a BMI ≥85th percentile. In comparison with the subset of the NHANES cohort who were obese (BMI ≥95th percentile), TODAY youth spent significantly more time being sedentary (difference averaging 56 minutes per day; P < .001) as assessed by accelerometry. Although moderate to vigorous activity levels in both obese cohorts for all age groups were exceptionally low, younger TODAY boys were still significantly less active than similarly aged NHANES youth. Comparisons between the TODAY girls and other investigations suggest that the TODAY girls also had relatively lower PA and fitness levels. Adolescents with type 2 diabetes from the large TODAY cohort appear to be less physically active and tend to spend more time being sedentary than similarly aged youth without diabetes identified from other large national investigations. Treatment efforts in adolescents with type 2 diabetes should include decreasing sitting along with efforts to increase PA levels.