With the development of digital technology, cyberbullying among college students has become the common manifestation of contemporary college students'' online deviance. Preventing and correcting cyberbullying among college students has become a hot issue of social concern. Based on the perspective of identity mobility, this paper explores the main manifestations and the causes of contemporary college students'' cyberbullying behavior. Contemporary college students'' cyberbullying behavior is based on their fluid identities and presents three main characteristics in cyberspace: "de-responsibilization", "emotional polarization", and "pan-entertainment tendency". Its main causes lie in the technical anonymity phenomenon of the online environment, the group polarization of online social interaction, and the subcultural pan-entertainment nature of online culture. Based on this, the paper proposes basic strategies for preventing and correcting cyberbullying among college students: carry out legal education on "anonymity does not equal exemption", clarifying the moral responsibility of college students; create positive and healthy online cultural activities for college students to forge moral consensus among them; establish a three-dimensional and collaborative online governance system to enhance college students'' communicative rationality.