Background: Standard neoadjuvant chemotherapy has not yet been established for patients with muscle-invasive bladder cancer (MIBC) who are ineligible for cisplatin (CDDP)-based chemotherapy. We conducted a propensity score analysis to evaluate the clinical significance of neoadjuvant gemcitabine and carboplatin (GCarbo) chemotherapy for CDDP-ineligible patients with MIBC. Methods: We enrolled 381 patients with MIBC, and retrospectively compared two cohorts of CDDP-ineligible patients with MIBC. The GCarbo cohort consisted of 63 patients, who received 2 courses of GCarbo consisting of 800 mg/m² gemcitabine on days 1, 8, and 15 and carboplatin with an area under the curve of 4 on day 2, prior to RC. The RC alone cohort consisted of 56 patients receiving RC without neoadjuvant or adjuvant chemotherapy. The endpoints were overall (OS), cancer-specific (CSS), and disease-free survival (DFS). The oncological outcomes were analyzed using log-rank test and multivariate Cox regression model. Results: Propensity score-matched analysis indicated 56 matched pairs from both groups. The 3-year OS rates were 77.9% for the GCarbo cohort and 50.7% for the RC alone cohort (P = 0.002). The 3-year CSS rates were 92.8% for the GCarbo cohort and 52.6% for RC alone group (P < 0.001). The 3-year DFS rates were 80.6% for the GCarbo cohort and 48.1% for the RC alone cohort (P = 0.005). Multivariate analysis revealed that GCarbo was an extremely strong predictor of improved survival. Conclusions: Although the present study is non-randomized, neoadjuvant GCarbo chemotherapy followed by immediate RC significantly improved OS, CSS, and DFS in CDDP-ineligible MIBC patients.