Little is known about the role of subjective sexual arousal within romantic relationships. The current paper addresses this limitation using a prospective study design that investigates the direct associations between subjective sexual arousal induced by a romantic partner (partner arousal) and arousal induced by pornography (porn arousal) on changes in relational outcomes. A total of 309 participants who were in a current romantic relationship completed measures of partner and porn arousal as well as relational outcomes (i.e., sexual satisfaction and relationship quality and stability) at baseline (T1) and completed a second assessment of relational outcomes 2months later (T2). Partner arousal was found to have no significant associations with changes in relational outcomes; however, porn arousal was associated with significant declines in sexual satisfaction and relationship quality and stability over a 2-month period. This paper is the first to examine how feeling sexually aroused by porn may impact relational outcomes for those in romantic relationships.