Abstract Background Nivolumab plus ipilimumab combination therapy is one of the standard therapies for untreated renal cell carcinoma patients with an International Metastatic Renal Cell Carcinoma Database Consortium intermediate/poor risk. We have previously reported the 1-year analysis results of the effectiveness and safety of nivolumab plus ipilimumab combination therapy in the real-world setting in Japan. Here, we report the effectiveness of nivolumab plus ipilimumab combination therapy and of second-line therapy, using 2-year analysis. Methods This retrospective observational study enrolled Japanese patients with previously untreated metastatic renal cell carcinoma who initiated nivolumab plus ipilimumab combination therapy between August 2018 and January 2019. Data were collected from patients’ medical records at baseline and at 3 months, 1 year and 2 years after the last enrollment. Results Of the 45 patients enrolled, 10 patients (22.2%) each had non-clear cell renal cell carcinoma and Eastern Cooperative Oncology Group performance status ≥2 at baseline. Median follow-up period was 24.0 months; objective response rate was 41.5%, with 6 patients achieving complete response; median progression-free survival was 17.8 months and 24-month progression-free survival and overall survival rates were 41.6 and 59.1%, respectively. Second-line therapy achieved an objective response rate of 20%; median progression-free survival was 9.8 months. Median progression-free survival 2 was 26.4 months. Conclusions The effectiveness of nivolumab plus ipilimumab combination therapy at 2-year analysis in the real-world setting in Japan was comparable to that reported in CheckMate 214. The current analysis also demonstrated the effectiveness of second-line therapy after nivolumab plus ipilimumab combination therapy.