Persons with mental illness smoke at rates two to four times higher than do persons without mental illness and comprise 30.9% of the U.S. tobacco market. Given the prevalence of mental illness and the known detrimental effects of tobacco, concerted efforts are needed to promote the use of evidence-based treatment options. We conducted a systematic review of studies that examined the impact of tobacco quitline interventions in this population. Results revealed an overall positive impact of cessation services delivered via a tobacco quitline. More research is needed to determine intervention components and patient characteristics that are associated with cessation success.