The aim of the present study is to examine the relationships between Internet addiction, subjective vitality, and subjective happiness. The participants were 328 university students who completed a questionnaire package that included the Online Cognition Scale, the Subjective Vitality Scale, and the Subjective Happiness Scale. According to the results, subjective vitality and subjective happiness were negatively predicted by Internet addiction. On the other hand, subjective happiness was positively predicted by subjective vitality. In addition, subjective vitality mediated the relationship between Internet addiction and subjective happiness. Results were discussed in light of the literature.