Abstract Background There are limited data regarding the impact of ethnicity among patients receiving immune checkpoint inhibitors. We evaluated real-world outcomes between Latinx and non-Latinx patients with metastatic renal-cell carcinoma (mRCC) treated with first-line nivolumab/ipilimumab within 2 different healthcare settings. Methods We performed a retrospective analysis of patients with mRCC who received nivolumab/ipilimumab within the Los Angeles County Department of Health Services (LAC-DHS), a safety-net healthcare system, and the City of Hope Comprehensive Cancer Center (COH), a tertiary oncology center, between January 1, 2015 and December 31, 2021. Progression-free survival (PFS) and overall survival (OS) were determined using the Kaplan-Meier method and covariates were adjusted using multivariate Cox proportional hazards regression. Results Of 94 patients, 40 patients (43%) were Latinx while the remainder were non-Latinx (44 pts [46%] White, 7 pts [7%] Asian, and 3 pts [3%] Other). Fifty (53%) and 44 (47%) patients received their care at COH and LAC-DHS, respectively. Most Latinx patients (95%) were treated at LAC-DHS, and most non-Latinx patients (89%) were treated at COH. Pooled analysis by ethnicity demonstrated significantly shorter PFS in Latinx versus non-Latinx patients (10.1 vs. 25.2 months, hazard ratios [HR] 3.61, 95% CI 1.96-6.66, P ≤ .01). Multivariate analysis revealed a HR of 3.41 (95% CI 1.31-8.84; P = .01). At a median follow-up of 11.0 months, the median OS was not reached in either arm at the time of data cutoff. Conclusion Latinx patients with mRCC had a shorter PFS treated with frontline nivolumab/ipilimumab compared to their non-Latinx counterparts. No difference was observed in OS although these data were immature. Larger studies are needed to further interrogate the social and economic determinants of ethnicity on clinical outcomes in mRCC.