Purpose: Children with autism spectrum disorder (ASD) without intellectual disability (ID) exhibit social and motor impairments and circumscribed interests/behaviors that contribute to lower physical activity (PA) levels. Despite the need for exercise interventions for these children, there is a dearth of evidence-based treatments. This study tested the feasibility of a high-intensity exercise program for children with ASD without ID, and associated changes in physical performance. Method: Fifty-eight children, ages 7-12 with ASD without ID participated. The intervention (5 weeks, 19 sessions, 60 mins ea.) was conducted during the summer. Each session was manualized (operationalized instructional procedure and curriculum) and targeted components of fitness and motor performance using skill development exercises, workouts, and game-related activities. Feasibility was assessed via fidelity (implementation accuracy), satisfaction surveys, attrition, and injuries. Physical performance was tested at baseline and posttest using measures of work production (completed rounds of an exercise circuit) and within-session activity levels (time in moderate-to-vigorous PA), and six exercise tests (sit and reach, push-ups, sit-ups, air squats, long jump, and PACER). Results: Results indicated high levels of fidelity (93.7%) and child and staff satisfaction, and no attrition or injuries, supporting the feasibility, tolerability, and safety of the protocol. Significant increases were found in work production and activity levels (ds 0.83 and 1.05, respectively) and on three exercise tests (sit ups, air squats, and long jump; ds 0.29-0.37). Conclusion: The exercise program was feasible and safe, and completion was associated with significant improvements in multiple areas of performance; a randomized controlled trial appears warranted.