The purpose of this study was to assess the safety and efficacy of Yttrium-90 radioembolization using in unresectable hepatocellular carcinoma. From 2017 to 2021, 32 patients with unresectable hepatocellular carcinoma, with mean tumor diameter about 7cm (21 males, 11 females; median age, 57.5 years of age), treated with Yttrium-90 radioembolization using resin microspheres were reviewed at pre-Yttrium-90 and post-Yttrium-90 follow-up. Tumor response was assessed according to the modified Response Evaluation Criteria in Solid Tumors. Outcomes including overall survival and progression-free survival were reported. Median follow-up was 18 months. At follow-up examinations at 3-, 6-, and 12-months follow-up, the overall survival rates were 94%, 87% and 59%, and the progression-free survival rates were 78%, 64% and 60%, respectively. Complete response, partial response, stable disease, and progressive disease were noted in 7 (21.9%), 14 (43.7%), 4 (12.5%), and 7 (21.9%) patients, respectively. The disease control rate was 78.1%, the objective response rate was 65.6%, and the successful downstage rate was 34.4% (11 of 32). Nine of thirty-two patients underwent resection or transplantation after Yttrium-90 radioembolization with 2-year overall survival being 100%. No serious adverse events occurred after Yttrium-90 treatment. Worse overall survival was related to the larger tumor, higher stage, Eastern Cooperative Oncology Group performance status, and Child-Pugh score. And worse progression-free survival was related to the higher tumor burden, and pre-Yttrium-90 serum α-fetoprotein level >100. Yttrium-90 Radioembolization can control hepatocellular carcinoma well even in advanced diseases. Patients successfully downstaging/bridging to resection or transplantation have excellent overall survival.