["Social Science Quarterly, Volume 102, Issue 4, Page 1743-1760, July 2021. ", "\n\nBackground\nThe relationship between smartphone addiction (SPA) and loneliness is examined in several studies, however, the mediating effects of the variables related to narcissism and the family on the relationship between SPA and loneliness are not yet available in the literature.\n\n\nObjective\nThe present study investigates the role of SPA on loneliness and the moderating effects of narcissistic personality and family belonging on loneliness.\n\n\nParticipants and Setting\nData required for research were obtained via an online survey from undergraduate students (n = 500) studying at a public university.\n\n\nMethods\nIn the study, the relationship between the variables was determined by path analysis.\n\n\nResults\nThe results of the path analysis show that there is a significant positive relationship between SPA and loneliness. According to the model, no significant relationship was found between narcissistic personality and family‐belonging level. There is a negative and significant mediation effect between SPA and narcissistic personality traits. There is a positive and significant mediation effect between SPA and family belonging. The results of the research are discussed with regard to university students and future directions.\n\n\nConclusions\nAccording to these research results, SPA predicts loneliness. As the level of family belonging decreases, SPA increases. The relationship between university students and their families and environments is among the variables that should be considered when evaluating SPA.\n\n"]