Background <p>Migrant children often experience greater anxiety and depression than their local peers due to challenges in adapting to urban life. Emotional resilience and mindfulness may serve as protective factors for mental health, but their influence on migrant children’s emotional well-being is not well understood. This study explored differences in anxiety, depression, mindfulness, and emotional resilience between migrant and local children and examined whether mindfulness moderates the relationship between emotional resilience and anxiety/depression.</p> Method <p>We conducted a cross-sectional survey of 695 children (aged 8–15 years; 396 local and 299 migrant). Participants completed standardized questionnaires measuring mindfulness, anxiety (GAD-7), depression (PHQ-9), and emotional resilience. Group differences were analyzed with chi-square tests (for anxiety/depression prevalence) and t-tests (for mean scores), and Pearson correlations were calculated for continuous variables. A moderated regression analysis (Hayes’s PROCESS macro) was performed to test the effect of mindfulness in moderating the relationship between emotional resilience and anxiety/depression.</p> Results <p>The results indicated that migrant children had higher rates and total scores of anxiety and depression compared to local children, while local children demonstrated slightly higher emotional resilience. No significant difference in mindfulness levels was found between the groups. Mindfulness was significantly negatively correlated with anxiety and depression and positively correlated with emotional resilience. Moreover, mindfulness moderated the relationship between emotional resilience and anxiety or depression, suggesting it consistently mitigated the negative impact of low emotional resilience.</p> Conclusion <p>These findings emphasize the critical role of mindfulness in supporting the mental health of children, particularly those from migrant backgrounds.</p>