Abstract: Aim: Drug use can have consequences for intimate relationships and partners’ behaviors can impact each other. We examined relationships between drug use and marital functioning among a cohort of current and former US Reserve and National Guard (R/NG) soldiers and their spouses. We sought to understand how soldier drug use impacts their partners’ marital functioning, and whether current versus former military status plays a role. Methods: Data from Operation: SAFETY, an ongoing longitudinal study of R/NG soldiers and spouses (N=418 couples). We examined the impact of the spouse’s drug use on their own marital functioning, independently and then controlling for their depression. Next, we examined how the soldier’s drug use impacted their spouse’s marital functioning one year later (cross-spouse), controlling for the spouse’s own depression and drug use. Finally, we added an interaction term to the cross-spouse model to examine the joint effects of soldier’s drug use and military status to understand if leaving the military affected the relationship between their drug use and their spouse’s marital functioning. Results: Among female spouses, their drug use was related to lower marital functioning (IRR: 0.92, 95% CI: 0.84, 0.99, p<.05), but was no longer significant after controlling for their depression. There were no main effects of soldier drug use on the spouse’s marital functioning. However, there was a significant interaction such that women whose husbands were still in the military and used drugs had the lowest levels of marital functioning (p<.05). Conclusions: Male soldier’s drug use negatively impacted their spouse’s marital functioning one year later, when the soldier was still serving in the military. Since drug use is illegal for current military service members and could result in dishonorable discharge, this may reflect conflict in the relationship over the potential risks and consequences of his drug use.