Objective. To assess the progression of dental caries among Malaysian infantry soldiers after 5 years in military service. Design. A retrospective cohort study with a self-administered questionnaire and a clinical oral examination. Result. Data were available for 173 (67.3%) soldiers. Mean decayed, missing, or filled teeth had increased significantly by 20.6% (P = .001) over 5 years. The highest increase was in the missing teeth component (+120%), followed by filled teeth (+23%). This was accompanied by a decrease in decayed teeth (–23.5%; P < .05). In terms of surfaces, mean decayed, missing, or filled surfaces, missing surfaces, and filled surfaces had increased significantly (P < .05). Caries experience was significantly associated with smoking status and rank (P < .05). Conclusion. Dental caries experience was worse after 5 years in military service compared with during recruitment, and there were more tooth extractions than restorations. Health promotion interventions are needed to prevent further tooth loss among soldiers.