BACKGROUND Smokeless tobacco (ST) use represents an important target for intervention in the U.S. military population because it impairs "military readiness" and harms the health of the military. This paper aims to provide a systematic review of ST studies conducted in the U.S. military population in order to assess the content of existing ST research in this population, provide estimates of prevalence and clinically relevant use patterns, and discuss how these findings might be used to guide future ST research among this population. METHODS We reviewed articles published through December 2010 using PubMed and PsycINFO databases, Google Scholar, and any relevant articles' reference lists. Inclusion criteria included focus on a U.S. military sample, English language, measured tobacco use, and ST prevalence was reported or could be calculated. To the extent possible, each article was coded for demographics, socioeconomic status, prevalence, amount, frequency, and length of use, and quit intentions/attempts. RESULTS Thirty-nine articles met criteria for inclusion. Less than half focused primarily on ST use among military personnel. The remaining studies measured ST use in the context of other behaviors. Findings related to clinically relevant behaviors included a need for more cohort and intervention studies, a better understanding of ST use in combination with cigarettes (i.e., concurrent use), and identifying risk factors for ST initiation and use. CONCLUSIONS ST use is prevalent among military personnel, as is concurrent use of cigarettes and ST. We provide a number of recommendations to guide future research in this important, yet understudied, area.