Background/Aims: Lenvatinib was recently approved as a first-line oral multikinase inhibitor for unresectable hepatocellular carcinoma (HCC). In this study, we aimed to compare the efficacy and safety of lenvatinib and sorafenib for the treatment of unresectable HCC in patients with prior failure of transarterial treatment. Methods: Between January 2019 and September 2020, 98 unresectable HCC patients treated with lenvatinib or sorafenib as salvage therapy were enrolled from five Korean university-affiliated hospitals. Progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and disease control rate were calculated to assess the antitumor response. Results: A total of 43 and 55 patients were treated with lenvatinib and sorafenib, respectively, as salvage therapy after the failure of transarterial treatments. The median PFS was 4.97 months in the lenvatinib group and 2.47 months in the sorafenib group ( p = 0.001, log-rank test). The ORR was significantly higher in the lenvatinib group (25.6%) than in the sorafenib group (3.6%, p = 0.002). Use of lenvatinib over sorafenib (hazard ratio: 0.359, 95% confidence interval: 0.203–0.635, p < 0.001) was the most significant factor for a favorable PFS after the failure of transarterial treatments in all enrolled patients. For favorable OS, achieving objective response was the significant factor (hazard ratio 0.356, 95% confidence interval: 0.132–0.957, p = 0.041). There were no significant differences in the safety profile between the two groups. Conclusions: In this real-world study, lenvatinib was demonstrated to be more efficacious than sorafenib as a salvage therapy for transarterial treatments in unresectable HCC.