Tibial stress fractures commonly occur in athletes and military recruits. This prospective, randomized, double-blind clinical study sought to determine whether pulsed ultrasound reduces tibial stress fracture healing time. Twenty-six midshipmen (43 tibial stress fractures) were randomized to pulsed ultrasound or placebo treatment. Twenty-minute daily treatments continued until patients were asymptomatic with signs of healing on plain radiographs. The groups were not significantly different in demographics, delay from symptom onset to diagnosis, missed treatment days, total number of treatments, or time to return to duty. Pulsed ultrasound did not significantly reduce the healing time for tibial stress fractures.