Social media have amplified and accelerated the ethical challenges that communicators, professional and otherwise, face worldwide. The work of ethical journalism, with a priority of truthful communication, offers a paradigm case for examining the broader challenges in the global social media network. The evolution of digital technologies and the attendant expansion of the communication network pose ethical difficulties for journalists connected with increased speed and volume of information, a diminished place in the network, and the cross-border nature of information flow. These challenges are exacerbated by intentional manipulation of social media, human-run or automated, in many countries including internal suppression by authoritarian regimes and foreign influence operations to spread misinformation. In addition, structural characteristics of social media platforms’ filtering and recommending algorithms pose ethical challenges for journalism and its role in fostering public discourse on social and political issues, although a number of studies have called aspects of the “filter bubble” hypothesis into question. Research in multiple countries, mostly in North America and Europe, has examined social media practices in journalism, including two issues central to social media ethics—verification and transparency—but ethical implications have seldom been discussed explicitly in the context of ethical theory. Since the 1980s and 1990s, scholarship focused on normative theorizing in relation to journalism has matured and become more multicultural and global. Scholars have articulated a number of ethical frameworks that could deepen analysis of the challenges of social media in the practice of journalism. However, the explicit implications of these frameworks for social media have largely gone unaddressed. A large topic of discussion in media ethics theory has been the possibility of universal or common principles globally, including a broadening of discussion of moral universals or common ground in media ethics beyond Western perspectives that have historically dominated the scholarship. In order to advance media ethics scholarship in the 21st-century environment of globally networked communication, in which journalists work among a host of other actors (well-intentioned, ill-intentioned, and automated), it is important for researchers to apply existing media ethics frameworks to social media practices. This application needs to address the challenges that social media create when crossing cultures, the common difficulties they pose worldwide for journalistic verification practices, and the responsibility of journalists for countering misinformation from malicious actors. It is also important to the further development of media ethics scholarship that future normative theorizing in the field—whether developing new frameworks or redeveloping current ones—consider journalistic responsibilities in relation to social media in the context of both the human and nonhuman actors in the communication network. The developing scholarly literature on the ethics of algorithms bears further attention from media ethics scholars for the ways it may provide perspectives that are complementary to existing media ethics frameworks that have focused on human actors and organizations.