Introduction: Systemic therapy is recommended for patients with Child-Pugh A in hepatocellular carcinoma (HCC). We analyzed the outcomes of a cohort of patients with HCC who received either sorafenib (Sor), lenvatinib (Len) or atezolizumab plus bevacizumab (Atezo + Bev) as first-line systemic therapy for HCC, with the aim of identifying prognostic factors for survival. Methods: A total of 825 patients with advanced HCC and Child-Pugh A or B received either Sor, Len or Atezo + Bev as first-line systemic therapy. Liver function was assessed according to the Child-Pugh score and the modified albumin-bilirubin (mALBI) grade. Results: Prognosis was analyzed according to liver function such as Child-Pugh classifications, scores, and mALBI grades that worsened with a decline in liver function (p <0.001 for all). A Child-Pugh score of 7 was a factor significantly associated with OS. In patients with a Child-Pugh score of 7, an mALBI grade of 3 was an independent predictor of OS. In Child-Pugh B patients with HCC, receiving Atezo + Bev was identified as a factor associated with PFS. Conclusion: Determining the hepatic reserve of patients with unresectable HCC might be useful for identifying patents suitable for systemic treatment for HCC. Atezo + Bev might prolong the PFS of patients with a Child-Pugh score of 7.