This study adopts China National Petroleum Corporation (CNPC) as a case to analyze its Corporate Social Responsibility (CSR) activities in transnational context. It first gives a comprehensive introduction to the significance and developmental trajectory of CSR in China to set up the research context. Next, it critically adopts Ditlev-Simonsen and Wenstop’s (2011) taxonomy of ethics rhetoric to analyze the ethical commitment and moral reasoning entailed in CNPC’s CSR reports in the consecutive years of 2008-2012, and contextualizes CNPC’s ethical disposition by comparing CNPC’s CSR performance with its western counterparts Royal Dutch Shell in the same period. The comparison also helps to shed lights on the convergence and divergence of Chinese and western CSR practiced transnationally. The findings reveal that compared with Shell’s ethics rhetoric deployed in its CSR communications, which focuses more on human rights and governance issues like anti-corruption and transparency, CNPC invokes more development related issues like fulfilling the basic needs of the local people. Although they all mainly base their ethics rhetoric on perspectives of benefit (B) and ethos (E), their underlying ethical reasoning is rather different. Besides, since Detlev-Simonsen and Wenstop’s framework follows a dominant business ethics approach, it is inadequate in analyzing ethics rhetoric from the perspective of care and relationship, an IV emerging, yet still marginal business ethics that has largely been ignored in CSR research. This study suggests that future studies can involve more comparative analyses, or examine more into the ethical aspects of CSR discourses other than corporate reports, especially from the “care and relationship” perspective.