The purpose of the study is to assess the safety and effectiveness of SCT-I10A in combination with SCT510 in patients with HCC who have not received prior systemic therapy.

Inclusion Criteria:

• Participants must have a diagnosis of HCC not suitable for radical surgery and/or local treatment，or progressed after surgery and/or local treatment.
• No prior systemic therapy for HCC(End of postoperative adjuvant chemotherapy for more than 6 months allowed).
• Child-Pugh ≤7 , no history of hepatic encephalopathy.
• Barcelona Clinic Liver Cancer stage B, not suitable for local treatment and BCLC C.
• At least one measurable lesion based on Recist1.1
• Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1.
• Adequate hematologic and organ function.

Exclusion Criteria:

• Local treatment or surgery for liver lesions within 4 weeks.
• Prior liver or other organ transplantation.
• Active Central nervous system (CNS) metastasis or leptomeningeal metastases.
• Gastrointestinal perforation and/or fistula or intraperitoneal abscess within 6 months prior to the start of study treatment.
• Hemorrhage tendency or high-risk for bleeding , severe coagulation disorders.
• Active known, or suspected autoimmune disease.
• Any condition that is not suitable for participate in this study as determined by investigator.