The positive or negative impacts corporate social responsibility (CSR) may have on business performance have drawn research interest. In recent years, the focus of research has shifted toward the link between CSR and corporate competitive advantage. Corporate competitive advantage is a multifaceted and holistic concept that captures more than just corporate financial performance. Building on the resource-based view (RBV), corporate competitive advantage construct theory, and CSR behavior theory, we explore how a firm's CSR engagement shapes its corporate competitive advantage. Our (...) analysis of a panel dataset of 64 companies with a top-100 CSR development index in China and 704 firm-year observations over the sample period from 2009 to 2019 reveals an inverse U-shaped relationship between CSR and corporate competitive advantage. This signifies that corporate competitive advantage first increases with CSR engagement but declines as it reaches a threshold level where CSR activities are beyond the affordability of the firm. We also examine how behaviors at various CSR engagement levels influence different dimensions of corporate competitive advantage. These results support a curvilinear relationship, explaining why many CSR strategies have been ineffective in the past. The findings may help guide corporate decisions and government policymaking on CSR. (shrink)