The aim of this study was to examine the mediating effect of social and enhancement motives between extroversion and SNS addiction. Participants of this study were 141 adults(female 101, male 40) in Gyungsangbuk-do province of South Korea. The scales of extroversion, SNS use motives, and SNS addiction were used. Bootstrap indirect mediation analysis revealed proximal use motive to be influential mechanisms through which distal traits affect SNS addiction. Specifically, enhancement motives mediated between extroversion and SNS addiction. However, social motives did not mediate between extroversion and SNS addiction. The limitations and implications of this study and suggestions for future study were discussed.