Objective <p>As societal pressures increase, many college students face social anxiety, especially those with adverse childhood experiences, which can lead to higher social anxiety in adulthood. Parental attachment and cyberbullying victimization may mediate this relationship, while resilience could alleviate the effects. This study, based on the stress-vulnerability model and attachment theory, investigates how adverse childhood experiences affect social anxiety among college students, with parental attachment and cyberbullying victimization as mediators and resilience as a moderator, forming a moderated chain mediation model.</p> Method <p>A random sample of 964 college students from various Chinese universities was selected. Standardized scales assessed parental attachment, cyberbullying victimization, resilience, adverse childhood experiences, and social anxiety. Structural equation modeling tested the proposed model, and multi-group analysis examined differences between single-parent and non-single-parent families.</p> Results <p>Adverse childhood experiences were significantly associated with higher social anxiety. Parental attachment and cyberbullying victimization played mediating roles, with resilience reducing the impact of adverse childhood experiences on social anxiety. In non-single-parent families, parental attachment more strongly protected against cyberbullying, whereas, in single-parent families, adverse childhood experiences had a more pronounced effect on cyberbullying victimization.</p> Conclusion <p>This study reveals the psychological mechanisms through which adverse childhood experiences contribute to social anxiety in college students, offering new insights and practical recommendations for preventing and treating social anxiety in university settings.</p>