Loneliness is a significant health concern that may be influenced by dispositional features. Pathological narcissism may elevate loneliness through aversive interpersonal behaviors and negative social appraisals. The present study examined two dimensions of pathological narcissism, along with five-factor personality traits, in relation to loneliness among 120 young adults. Loneliness was also examined as a mediator between pathological narcissism and satisfaction with life. Narcissistic grandiosity and narcissistic vulnerability were both significantly associated with loneliness. Multiple regression analysis, including five-factor traits, revealed narcissistic vulnerability to be uniquely associated with loneliness, along with neuroticism. Mediation analysis also found an indirect effect of narcissistic vulnerability on reduced satisfaction with life, through loneliness as a mediator. These preliminary findings point to future research needs and potential clinical consideration of narcissistic vulnerability as a dispositional risk factor for loneliness.