The psychological mechanisms that potentially underlie the negative correlation between narcissism and relationship satisfaction are unknown. This study examined the potential mediating role of perfectionistic self-presentation in the association between grandiose and vulnerable narcissistic traits and relationship satisfaction. The Actor-Partner Interdependence Mediation Model was used to examine these associations in 344 nonclinical heterosexual couples. Mediated actor effects of men’s grandiose narcissism (GN) on their own relationship satisfaction emerged as well as direct effects of women’s vulnerable narcissism (VN) on their own satisfaction. Women’s relationship satisfaction was influenced by their male partner’s VN. Male partners of women high in GN reported lower relationship satisfaction. The results uniquely illustrate how narcissism focused on a need to seem perfect can undermine relationship satisfaction.