ObjectiveTo explore the safety and effectiveness of transarterial chemoembolization (TACE) combined with lenvatinib and programmed cell death protein-1 (PD-1) antibody in the conversion resection for intermediate and advanced unresectable hepatocellular carcinoma (HCC), and to provide new treatment strategies for the treatment of intermediate and advanced unresectable HCC. MethodThirty-eight intermediate and advanced unresectable HCC patients treated at West China Hospital of Sichuan University from October 2020 to June 2021 were prospectively included in our study, all patients treated with TACE + lenvatinib + PD-1 antibody, and the clinical data of these 38 patients were summarized. ResultsThe last evaluation time for the 38 patients was October 20, 2021. According to the mRECIST standard for tumor efficacy evaluation, the objective response rate was 84.2% (32/38), the disease control rate was 94.7% (36/38); the conversion success rate based on imaging was 55.3% (21/38), the actual conversion resection rate was 52.6% (20/38). The incidence of adverse events was 100%, of which 22 patients had grade 3 adverse events, and there was no ≥ grade 4 adverse events. All patients were followed up, the follow-up time was 16–52 weeks, and the median follow-up time was 33.5 weeks. During the follow-up period, only two patients had tumor progression, of which one patient died due to disease progression, and there was no postoperative recurrence. ConclusionsLenvatinib combined with TACE and PD-1 antibody is safe for the treatment of intermediate and advanced unresectable HCC. Triple therapy can achieve satisfactory conversion resection rate of intermediate and advanced unresectable HCC, which will provide a new treatment strategy for it.