ABSTRACT Although corporate social responsibility (CSR) authenticity and customer citizenship behavior (CCB) are of great importance to the long-term success of businesses in the hospitality sector, the linkage between them has been an under-researched aspect. Based on social exchange theory and cognitive appraisal theory, a research model is developed to examine whether and how perceived CSR authenticity promotes customer citizenship behavior (CCB). The data was collected from 313 customers of the fast food restaurants in Taiwan and analyzed using PLS-SEM. The findings reveal that perceived CSR authenticity positively and directly impacts CCB. Further, this relationship is mediated by emotional attachment and feelings of gratitude and is positively moderated by altruism. This study contributes to the extant literature by uncovering the mechanisms through which CSR authenticity impacts CCB and provides crucial implications that help hospitality firms formulate more effective CSR strategies based on the perceived authenticity of their CSR activities.