Although breast cancer treatment is associated with improved survival rates, it is also associated with numerous side effects, which can decrease overall quality of life for patients. Recent research indicates acupuncture may be useful in decreasing the incidence and duration of some side effects associated with cancer treatment. To assess the evidence surrounding the role of acupuncture in treating side effects associated with breast cancer treatment. Systematic review based on search of PubMed, EMBASE (1996 to 2009 week 17), AMED (1985 to April 2009), and Ovid MEDLINE (1996 to April 2009) databases for relevant studies published up to April 2009. Authors of recent studies were contacted to determine if additional studies were taking place. Fourteen articles were independently appraised by 4 blinded reviewers. Twelve studies met inclusion criteria: 9 investigated effects of traditional acupuncture and 3 addressed electroacupuncture. Seven different side effects were examined (hot flashes, fatigue, pain, dyspnea, psychological well-being, decreased range of motion with lymphedema, and emesis). The findings support the potential use of traditional acupuncture to decrease hot flashes, fatigue, and pain, whereas electroacupuncture may be useful in treating emesis and hot flashes. There is a paucity of high-quality evidence to support the use of acupuncture to treat dyspnea, emesis, and decreased range of motion with lymphedema or to improve psychological well-being. Current evidence suggests that traditional acupuncture may be useful in reducing hot flashes, fatigue, and pain, whereas electroacupuncture may be useful in treating emesis and hot flashes. Due to limitations in study designs and heterogeneity in treatment protocols, results should be viewed with caution and combined with clinical reasoning.