Objective: This study examined age-related differences in general medical and mental health risk factors for veterans participating in the U.S. Department of Veterans Affairs (VA) Grant Per Diem (GPD) transitional supportive housing program. The subpopulation of older homeless veterans is growing, and little is known about the implications of this fact for health care providers and for supportive programs intended to meet homeless veterans’ needs. Methods: Data were obtained from the VA records of all veterans (N=40,820) who used the GPD program during fiscal years 2003 to 2009. Unconditional adjusted and unadjusted odds ratios for general medical and psychiatric characteristics were calculated and were the primary study focus. Significant predictors of homeless program completion assessed from univariate models were then evaluated in multivariate models. Results: Younger (,55) and older ($55) homeless veterans reported an equal number of days homeless before enrollment.Younger veterans averaged19 fewer days in GPD. Older veterans had more general medical problems and approximately $500 more in program costs. Conclusions: Findings from this study indicate that older homeless veterans are at increased risk of serious medical problems. This group is especially vulnerable to experiencing negative consequences related to homelessness. Addressing these complex needs will allow the VA to provide enhanced care to older homeless veterans.