Background: Combining lenvatinib (a multikinase inhibitor) with programmed cell death protein-1 (PD-1) inhibitor has been explored in Unresectable hepatocellular carcinoma (uHCC) in phase 1b trials. This study aimed to investigate the real-word efficacy and safety of lenvatinib plus PD-1 inhibitor for large Chinese patients uHCC cohorts. Methods: BCLC stage B or C uHCC patients were included. Data was collected from Oct 2017 to Nov 2021 retrospectively. Patients were treated with lenvatinib and PD-1 inhibitor (pembrolizumab or nivolumab or camrelizumab or sintilimab or toripalimab or tislelizumab). The primary endpoint was overall survival (OS) and secondary endpoints were progression-free survival (PFS) and objective response rate (ORR) evaluated by RECIST v1.1 criteria. Adverse events (AEs) were assessed using CTCAE v5.0. Prognostic factors of survival were also analyzed. Results: 378 uHCC patients of BCLC stage B (12.7%) and C (87.3%) from two medical centers were included in China. The median age was 55 (range 18-89) years and 86.5% patients were male. ECOG scores were 0 (43.7%), 1 (43.4%) and 2 (13.0%), while Child-pugh grade were A (77.5%) and B (22.5%) respectively. The median OS was 17.8 (95% CI 14.0-21.6) months. The median PFS was 6.9 (95% CI 6.0-7.9) months. The best objective response rate (ORR) and disease control rate (DCR) was 74/378 (19.6%) and 278/378 (73.5%) respectively. Child-pugh grade (A vs. B), ECOG score (0 vs. 1-2), BCLC stage (B vs. C) and achieve response (yes vs. no) were the prognostic factors for both OS and PFS. All (100%) experienced all-grade adverse events (AE). The most frequent AEs were fatigue, diarrhea, hypertension, decreased appetite. The most common ≥Grade 3 AEs were hypertension (13.2%), fatigue (7.1%), decreased platelet count (6.3%), increased blood bilirubin (6.1%), diarrhea (6.1%) and gastrointestinal hemorrhage (4.8%). Conclusions: This real-world study of lenvatinib plus PD-1 inhibitors achieved long survival and considerable ORR for uHCC patients in China. The tolerability of combination therapy was acceptable but should be still monitored closely. Clinical trial information: NCT03892577.