Friedrich Kittler is an important media theorist in Germany. He crossed the barrier between humanity and technology, and constructed unique media theory which echoes North American media ecology. Advancing Foucault’s discourse theory, he used “discourse networks” as a key concept, and analyzed the leading media, discourse networks and their influences on culture and society in the two discourse networks periods in Germany. Kittler focused on the dialectic relationship between media as the base and discourse networks as the superstructure, and he found that the interaction between the media and discourse networks was a driving force of civilization. This paper argues that this dialectic could be regarded as the theory of “media materialism”. Rethinking Kittler’s “discourse networks” means that we should broaden the research horizon and renovate research paradigm of contemporary Chinese communication studies.