Previous studies have implicated significant differences between military members and civilians with regard to violent behavior, including suicide, domestic violence, and harm to others, but none have examined military murder-suicide. This study sought to determine whether there were meaningful differences between military and civilian murder-suicide perpetrators. Using data from the Center for Disease Control’s (CDC) National Violent Death Reporting System (NVDRS), military (n = 259) and civilian (n = 259) murder-suicide perpetrators were compared on a number of demographic, psychological, and contextual factors using chi-square analyses. Logistic regression was used to determine which variables predicted membership to the military or civilian perpetrator groups. Military murder-suicide perpetrators were more likely to be older, have physical health problems, be currently or formerly married, less likely to abuse substances, and to exhibit significantly different motives than civilian perpetrators. Logistic regression revealed that membership to the military, rather than the civilian, perpetrator group was predicted by age, physical health problems, and declining heath motive—reflecting the significance of a more than 15-year difference in mean age between the two groups. Findings point to the need to tailor suicide risk assessments to include questions specific to murder-suicide, to assess attitudes toward murder-suicide, and to the importance of assessing suicide and violence risk in older adult military populations.