Evidence indicating that exercise benefits mental health symptoms across a range of mental health diagnoses spans decades of scientific literature; however, fewer studies have examined the impact of exercise on posttraumatic stress disorder (PTSD). Exercise is an accessible, cost-effective, and scalable treatment option that has the potential to improve both physiological and psychological symptoms among individuals with PTSD. The purpose of this chapter is to review empirical literature on the role of exercise in the treatment of PTSD. Researchers have demonstrated that exercise improves PTSD symptoms as both a stand-alone treatment and as an adjunct to cognitive behavioral and trauma-focused therapies. Additional research is needed to clarify mechanisms that account for the impacts of exercise on PTSD and to identify which components of exercise (e.g., type of exercise, dose, intensity, frequency) are the most beneficial.