According to IMpower133 and CASPIAN, anti-PD-L1 blockades combined with etoposide and platinum (EP) were the conventional first-line therapy for extensive-stage small-cell lung cancer (ES-SCLC). For a study, researchers sought to look into the clinical efficacy of first-line anti-PD-L1 blockades combined with EP for ES-SCLC with BMs. Patients with newly diagnosed ES-SCLC and baseline BM verified by CT or MRI at Cancer Hospital and Institute were involved in the study between 2017 and 2021. Patients were divided into two groups: anti-PD-L1+EP and EP, depending on whether they were given anti-PD-L1 blockades (atezolizumab or durvalumab). RECIST 1.1 was used to measure response, and Kaplan-Meier and log-rank tests were used for survival analyses. The current study enrolled a total of 56 participants. The anti-PD-L1+EP group received 18 points, while the EP group received 38. The average period of follow-up was 18.17 months. In the two groups, the overall response rate (ORR) was 72.22% vs. 78.95% (P=0.83), and the disease control rate (DCR) was 100% vs. 97.37%. In the case of BMs, the intracranial ORR and DCR were 50.00% vs. 68.42% (P=0.18) and 72.22% versus 78.95% (P=0.83), respectively. Anti-PD-L1 blockades increased progression-free survival (PFS) numerically, but not statistically (median: 9.4m vs 7.3m, P=0.146, HR=0.63 (95% CI, 0.35-1.13)). There was no improvement in intracranial PFS (median: 8.2m vs 7.9m, P=0. 943, HR=1.02 (0.53-2.00)). Anti-PD-L1 blockades, on the other hand, significantly increased overall survival (median: NR versus 15.53m, P=0.012, HR=0.20 (0.09-0.46)). Investigators discovered that adding first-line anti-PD-L1 blockades to EP resulted in a significant survival improvement for ES-SCLC with BMs compared to EP alone.