Military personnel are more than twice as likely as civilians to use smokeless tobacco (ST), and recent studies indicate that military prevalence rates are rising. However, few studies have examined factors related to ST use in the military. The present study evaluated the characteristics of ST use in 785 active duty military personnel. The results indicated that the average age of initiation was 17.7 years, participants had used ST for 12.3 years, and they used approximately four tins or pouches of tobacco per week. Army personnel were more likely than Air Force personnel to be older, to have used ST longer, and to be heavier users. Officers had used ST longer than enlisted personnel and were more likely to have had a recent quit attempt. Enlisted personnel were more than three times as likely to report concurrent cigarette smoking. These results indicate that there are significant differences in ST use patterns in military personnel, and cessation programs should be tailored to meet these differences.