Existing studies have established that socially responsible human resource management (SRHRM) positively affects employee outcomes. However, all of these investigations overlook the impact of SRHRM on employee thriving, a positive psychological state that may contribute to organizations’ long-term sustainability. Guided by ethical climate theory and the multi-experience model of ethical climate, we investigate whether, how, and when SRHRM improves employees’ thriving at work. Using a scenario-based experiment (Study 1, a 2 × 2 design) and a multi-wave field study (Study 2), we find that SRHRM positively predicts employees’ thriving at work, and this relationship is mediated by other-focused and self-focused climates. Furthermore, the relationship between SRHRM and the two types of ethical climates is strengthened by promotion-focused ethical leadership but weakened by prevention-focused ethical leadership. Moreover, the indirect relationship between SRHRM and employees’ thriving at work via the two types of ethical climates is strengthened by promotion-focused ethical leadership but weakened by prevention-focused ethical leadership. Our study extends SRHRM literature and meaningfully guides organizations that aim to sustain a thriving workforce.