Background: Eating disorders are a group of psychiatric disorders where the patient who is affected has disturbed eating habits or weight control behaviour. Eating disorders are severe with somatic complications and psychiatric comorbidity. There aren´t optimized treatment methods for eating disorders, and therefore it is important to search for new treatment methods so that people with eating disorders in the future can receive better treatment. In this thesis, the goal was to find and evaluate the research done on the use of physical activity as a treatment method for eating disorders. Material: A literature search in PubMed gave 522 hits. After excluding the articles which did not meet the inclusion criteria, 12 articles where included in this thesis. Results: The studies focusing on patients with anorexia found no adverse effects of physical activity as intervention. The intervention did not affect weight or other outcome measures in a negative manner. The studies focusing on people with binge-eating disorder implicated that physical activity led to fewer binge eating episodes. One study focused on patients with bulimia, and it indicated that physical activity was more effective than cognitive behavioural therapy when it came to reducing the frequency of binge-eating episodes. Discussion: Few of the studies could show statistically significant improvements between the intervention group and control group by using physical activity in the treatment of eating disorders. Further research is needed to determine whether physical activity as treatment should be offered to patients with eating disorders in the future.