AbstractCyberbullying is considered a major threat to adolescent anxiety. In this study, we aim to explore the simultaneous effects of cyberbullying victimization and perpetration on youth anxiety. Building on the childhood adversity model and the vulnerability‐stress model, we test the model wherein cyberbullying exposure is linked with cyberostracism, which in turn is expected to be associated with an increase in anxiety. We collected data from 1115 Chinese youth aged 11–19 years based on the stratified random sampling method. Structure equation modelling was conducted in Amos 26.0 to examine the proposed theoretical model. The findings suggested that compared with cyberbullying perpetration, the experience of cyberbullying victimization led to a significantly higher risk of youth anxiety. Multiple mediation analyses revealed that the three dimensions of cyberostracism, namely cyber direct excluded, cyber indirect excluded and cyber ignored, mediated the association of cyberbullying victimization and perpetration with youth anxiety. These results indicate that cyberostracism could be a risk factor for youth anxiety, thus providing new direction regarding intervention programs to reduce anxiety symptoms in adolescents.