Sexual subjectivity is a central feature of healthy sexuality that is believed to shape and be shaped by relationship experiences. However, no studies have examined sexual subjectivity within a dyadic context. The current study examined partner similarity in sexual subjectivity within 75 heterosexual couples and associations with sexual relationship functioning using actor-partner interdependence models. Within couples, partners’ scores were significantly correlated on three of five elements of sexual subjectivity and showed similar mean levels on four of the five elements. Men's and women's sexual self-efficacy were positively associated with their own sexual communication. Other associations varied by gender. Men's sexual body esteem and entitlement to self-pleasure predicted their reports of sexual relationship functioning, and women's entitlement to pleasure from partners and sexual reflection predicted their reports of relationship functioning. Few partner effects were observed. Findings suggest that partners’ sexual subjectivity is relevant for dyadic functioning in emerging adulthood. Longitudinal research is needed to examine how experiences within and across relationships contribute to the development of sexual self-concepts and sexual functioning.