While prior research generally acknowledges the positive effect of corporate philanthropy (CP) on firm performance, the underlying mechanisms regarding how or why CP leads to better financial performance remain unclear. We argue that employees as an influential firm stakeholder group may act as an important factor in realizing the value of CP. We specifically ground this study in social identity theory to investigate whether or not employees support CP by increasing labor productivity, as well as whether a firm's salary level and market visibility will moderate such an effect. Evidence from Chinese listed firms suggests that CP positively influences labor productivity. In addition, self-compared salaries and firm visibility strengthen the link between CP and labor productivity, suggesting that the value of CP depends on the support of key stakeholders such as employees.