Purpose: The aim of the present review was to determine effects of strength exercise on secondary lymphedema in breast cancer patients. Methods: Research was conducted by using the databases PubMed/Medline and Embase. Randomized controlled trials published from January 1966 to May 2015 investigating the effects of resistance exercise on breast cancer patients with or at risk of secondary lymphedema in accordance with the American College of Sports Medicine exercise guidelines for cancer survivors were included in the present study. Results: Nine original articles with a total of 957 patients met the inclusion criteria. None of the included articles showed adverse effects of a resistance exercise intervention on lymphedema status. In all included studies, resistance exercise intensity was described as moderate to high. Conclusions: Strength exercise seems not to have negative effects on lymphedema status or might not increase risk of development of lymphedema in breast cancer patients. Further research is needed in order to investigate the effects of resistance exercise for patients suffering from lymphedema. Keywords: Breast cancer; Medical training therapy; Resistance exercise; Secondary lymphedema; Strength.