Observational research has shown that the physical activity levels of survivors of hematological cancer are low, with deleterious health consequences. This review summarizes the research on exercise interventions in adult and pediatric hematological cancer survivors. We searched MEDLINE, SPORTDiscus, CINAHL, Embase, Cochrane and PEDro through September 2009 for exercise intervention studies in children and adults with any type of hematological cancer. In the 24 adult intervention studies reviewed, we found strong evidence (that is, X3 high-quality studies and X75% reporting a significant benefit) for a benefit on body composition. Weak, but promising, evidence (X3 high-quality studies, but o75% reporting a significant benefit) was found for cardiorespiratory fitness, fatigue, muscle strength, physical functioning and quality of life. In pediatric interventions (13 studies), we found strong evidence for a benefit on muscle strength and cardiorespiratory fitness, particularly, if training was conducted in the hospital setting. Evidence is weak for ankle dorsiflexion, physical functioning and body composition. No exerciserelated risks were identified in adults or children studies. Though more randomized controlled trials are needed, a growing body of literature supports the notion that regular physical activity is safe and has potential benefits for both adult and pediatric hematological cancer survivors.