We investigated the mediating role of social support in the relationship between gratitude and loneliness. Participants were 728 Chinese students, from 6 universities, who completed 3 psychometric scales: the Gratitude Questionnaire-6, the UCLA Loneliness Scale (version 3), and the Social Support Rating Scale. Both gratitude and social support exerted protective effects against loneliness, and social support partially mediated the relationship between gratitude and loneliness. The practical implication of this research is that gratitude promotes social support and, thus, can protect individuals against loneliness.