This study examines manifestations of verbal aggression in an intergroup context between Mainland Chinese and Taiwanese on computer-mediated communication (CMC) discussion boards. We examine the role of perceptions of national identity and face in occasioning instances of aggression in Sino-Taiwanese online interactions. It will be argued that there is a fundamental difference between Mainland Chinese and Taiwanese ways of displaying aggression when discussing cross-Strait issues. While the Taiwanese use abusive terms in order to dissociate themselves from the Mainland Chinese in online discourse, the latter tend to associate themselves with Taiwanese through terms that subsume Taiwanese claims to a national identity within a broader pan-Chinese identity, thereby implicitly displaying a social claim of sovereignty and cultural supremacy over Taiwan. We argue that these differences can be traced to evaluations by Taiwanese of these associative moves as threatening to their perceived national face.