Background <p>Hikikomori is a phenomenon of social isolation characterized by an individual’s intentional and prolonged withdrawal from social life, and it has increasingly drawn global scholarly attention. In Turkey, the limited number of empirical studies on hikikomori underscores the importance of examining its psychological determinants among young adults. This study aims to analyze the relationships between depression, psychological resilience, and hikikomori-related tendencies in individuals aged 18 to 34, and to test the mediating role of psychological resilience in these associations.</p> Methods <p>The study employed a quantitative, cross-sectional design and included 776 young adults recruited through convenience sampling. Participants completed the Beck Depression Inventory, the Brief Resilience Scale, and the Adaptive Behaviors Scale for Hikikomori Self-Report. Data were analyzed using SPSS 25.0, and mediation analysis was conducted using Pearson correlation and Hayes’ PROCESS macro (Model 4).</p> Results <p>Higher levels of depression were associated with an increase in hikikomori-related withdrawal behaviors, whereas higher levels of psychological resilience were related to more adaptive functioning. Psychological resilience significantly mediated the association between depression and hikikomori tendencies, indicating that depression influences social withdrawal partly through its impact on resilience.</p> Conclusions <p>The findings suggest that psychological resilience functions as a protective mechanism against social withdrawal among young adults. Strengthening resilience may therefore serve as an important target for preventive and therapeutic interventions. These results highlight the value of resilience-focused approaches within youth mental health policies and clinical practice.</p>