Background <p>Suicidal risk among university students remains a pressing public health concern, particularly in high-stress border contexts. While depressive symptoms are well-established correlates of suicidal risk, the adjusted association of psychological inflexibility and the potential roles of resilience and perceived social support remain underexplored among university students in structurally stressed regions.</p> Objective <p>This study examined whether psychological inflexibility was independently associated with suicidal risk beyond depressive symptoms and assessed whether resilience and perceived social support statistically accounted for indirect associations between psychological inflexibility and suicidal risk, and whether these pathways differed by sex.</p> Methods <p>A cross-sectional survey was conducted among 385 university students (M_age = 27.45, SD = 8.15) using snowball sampling. Participants completed validated measures of depressive symptoms, psychological inflexibility, resilience, perceived social support, and suicidal risk. Pearson correlations, simultaneous multiple regression, and moderated mediation analyses (PROCESS Model 7; 5,000 bootstrap resamples) were conducted.</p> Results <p>Suicidal risk was strongly positively correlated with depressive symptoms (<i>r</i> = .813, <i>p</i> &lt; .001) and psychological inflexibility (<i>r</i> = .701, <i>p</i> &lt; .001) and negatively correlated with perceived social support (<i>r</i> = -.448, <i>p</i> &lt; .001) and resilience (<i>r</i> = -.118, <i>p</i> = .020). In multivariable regression (<i>R</i>² = .739), depressive symptoms (β = .607, <i>p</i> &lt; .001) and psychological inflexibility (β = .294, <i>p</i> &lt; .001) showed the strongest adjusted associations with suicidal risk; however, resilience and perceived social support were not independently associated with suicidal risk in adjusted models. Moderated mediation analyses indicated no significant statistical indirect associations through resilience or perceived social support, and the indices of moderated mediation by sex were not significant.</p> Conclusions <p>Depressive symptoms and psychological inflexibility were the key adjusted correlates of suicidal risk in this border-region sample. Findings suggest that psychological inflexibility may represent a clinically relevant and potentially modifiable correlate of suicidal risk. However, longitudinal studies are needed to clarify temporal and causal pathways.</p>