Smartphone addiction is an increasingly severe issue in modern society, particularly impacting the mental health of college students during the COVID-19 pandemic. This study aims to explore the relationship between smartphone addiction and mental health issues among college students, and the mediating and moderating roles of psychological resilience and parental attachment. We employed a cross-sectional study design with 100,097 college Chinese students to examine the relationships between smartphone addiction, mental health (anxiety and depression), and the mediating role of psychological resilience. Parental attachment was assessed as a moderator within these relationships. Data were analyzed using multiple regression and mediation/moderation models, controlling for relevant covariates. Our findings revealed a significant positive correlation between smartphone addiction and both anxiety and depression. Psychological resilience mediated these relationships, suggesting that higher resilience levels can mitigate the negative psychological impacts of smartphone addiction. Additionally, parental attachment moderated the effects of smartphone addiction on psychological outcomes; stronger attachment was associated with less pronounced effects of addiction on anxiety and depression. Specifically, for students with low parental attachment, the predictive effect of smartphone addiction on anxiety and depression was more pronounced, whereas higher attachment levels were protective.
