CSP can be categorized into two dimensions: social dimension and regulatory dimension. As firms internationalize, institutions relating to the social dimension of CSP diversify across nation. While in its regulatory dimension, institutions tend to converge with internationalization. To the extent that institutional diversity decreases CSP while institutional convergence increases CSP, internationalization is expected to positively influence the regulatory dimension of CSP, but negatively influence the social dimension of CSP. Analyzing a sample of 2,138 U.S. public firms from 2003-2011, we confirm that internationalization negatively influence the social dimension of CSP, but positively influence the environment and governance domains of CSP. Additionally, the findings indicate that country-level institutional diversity and country-level CSR are two moderators of the relationship between internationalization and CSP.