<p>Research on cultural differences in the experience of loneliness often conceptualizes culture as a general inclination or disposition—such as the distinction between collectivist and individualistic cultures—typically manifested at an aggregate, usually national, level. Moreover, the mediating mechanisms between cultural factors and reported loneliness remain understudied. To examine whether and how more specific cultural beliefs and practices—those in which ordinary individuals are actively engaged in their daily lives—relate to loneliness, we focus on a distinctive, indigenous, and socially influential cultural tradition in mainland China: ancestor worship. Drawing on data from the Chinese Cultural Values Survey, this article identifies a robust and significant negative association between engagement in ancestor worship and feeling of loneliness. Compared to the belief dimension, the behavioral dimension of ancestor worship exerts a stronger effect in reducing loneliness. Ancestor worship alleviates loneliness by fostering family support, reinforcing moral alignment with parents, and encouraging intense interpersonal interactions during rituals. In addition, the behavioral aspect of ancestor worship mitigates loneliness by enhancing kinship identification and eliciting emotional arousal during ritual practices. This study contributes to the literature on culture and loneliness by presenting the case of China and highlighting the relevance of ancestor worship—a deeply rooted traditional culture in China and many other societies.</p>