Objective The promotion of healthy lifestyles among persons with serious mental illness is an integral part of their recovery. The aims of this systematic literature review were to rate the methodological quality of lifestyle intervention outcome studies for persons with serious mental illness, summarize intervention strategies, examine physical health outcomes, and evaluate the inclusion of racial and ethnic minority groups in these studies. Methods Electronic bibliographic database searches were performed to locate studies conducted in the United States. Articles written in English and published in peer-reviewed journals between 1980 and 2009 were included. The authors used a standardized instrument to rate studies' methodological quality. Results Twenty-three articles were reviewed. Based on studies' methodological quality, three levels of evidence were found: single-group reports, quasi-experimental studies, and randomized controlled trials. Most interventions used behavioral techniques to improve dietary habits and increase physical activity. Twelve studies reported significant improvements in either weight loss or metabolic syndrome risk factors associated with receiving a lifestyle intervention. Persons from racial and ethnic minority groups were underrepresented, especially Hispanics and Asian Americans. Only one study included non–English-speaking participants. Conclusions Lifestyle interventions adapted to persons with serious mental illness show promise in reducing weight loss and some risk factors for metabolic syndrome. The under-representation of persons from racial or ethnic minority groups in this literature limits its generalizability. Implications for research and practice are discussed.