OBJECTIVE: Social determinants of health (SDOH) impact cancer outcomes. The CDC Social Vulnerability Index (SVI) integrates scores for four neighborhood-based SDOH domains (socioeconomic status, household characteristics, minority status, and housing type/transportation) to assess neighborhood social vulnerability (NSV). While NSV has been associated with overall cancer mortality and lung, breast, colon, and endometrial cancer-specific mortality, the relationship between NSV as defined by the SVI and ovarian cancer outcomes remains unknown. METHODS: We used data from 177 patients enrolled in an observational ovarian cancer cohort study from October 2012 through September 2022. All patients underwent debulking surgery and completed an entire course of standard-of-care platinum-based chemotherapy. Follow-up was completed through May 2024. SVI was calculated using census tract at diagnosis. High NSV was defined as SVI in the top quartile of the cohort. Cox proportional hazard models assessed the association between NSV and progression-free (PFS) and overall (OS) survival. RESULTS: After accounting for demographic and clinical factors, high NSV was associated with significantly worse PFS (HR:2.31 [95% CI:1.48-3.61]; P < 0.001) and OS (HR:1.79 [95% CI:1.10-2.92]; P = 0.02), with neighborhood socioeconomic status associated with significantly worse PFS (HR:2.29 [95% CI:1.47-3.56]; P < 0.001) and OS (HR:1.71 [95% CI:1.04-2.80]; P = 0.03). Neighborhood housing type/transportation was also associated with significantly worse PFS (HR:1.65 [95% CI:1.07-2.55]; P = 0.02) and trended towards worse OS (HR:1.43 [95% CI: 0.80-2.33]). CONCLUSION AND RELEVANCE: Higher neighborhood social vulnerability is associated with worse outcomes among ovarian cancer patients. Validating these results in a population-based cohort and assessing programs to reduce neighborhood social vulnerability to improve ovarian cancer outcomes is warranted.