BackgroundBreast cancer patients experience significant psychological distress and marital strain during treatment. Psychological resilience may protect marital adjustment through emotional pathways, yet evidence of serial mediation mechanisms remains limited in nursing research.ObjectiveTo examine anxiety and depression as serial mediators between psychological resilience and marital adjustment.MethodsA multicenter cross-sectional study recruited 408 breast cancer patients from oncology departments in Shenzhen, Beijing, and Hebei. Standardized instruments assessed psychological resilience (Connor-Davidson Resilience Scale, CD-RISC), anxiety/depression (Hospital Anxiety and Depression Scale, HADS), and marital adjustment (Dyadic Adjustment Scale, DAS). Serial mediation analysis (PROCESS Macro Model 6) with 5,000 bootstrap resamples was conducted, adjusting for 15 clinical and sociodemographic covariates.ResultsPsychological resilience significantly correlated with marital adjustment (r = 0.295, p < 0.001). In the adjusted model, the total indirect effect was significant (b = 0.514, 95% CI [0.211, 0.839]), accounting for 53.65% of the total effect. The serial indirect pathway (resilience → anxiety → depression → marital adjustment) was significant (b = 0.219, 95% CI [0.069, 0.403]), explaining 22.86% of the total effect. The simple indirect pathway through depression was also significant (b = 0.153, 95% CI [0.047, 0.292]), while the pathway through anxiety alone was not. The direct effect remained significant (b = 0.444, 95% CI [0.076, 0.812]).ConclusionPsychological resilience is positively associated with marital adjustment through sequential associations with lower anxiety and depression. Oncology nurses should implement resilience-focused psychoeducation and couples’ communication training, particularly targeting anxiety in the early treatment phase, to enhance patients’ perceived marital adjustment.