To evaluate the efficacy of the C-to-G basic group editor (CGBE) Td-CGBE-NG in targeted knockout of the proprotein convertase subtilisin/kexin type 9 (PCSK9) genes of huh-7 hepatocellular carcinoma cells based on the reference of CBE (AncBE4max). Methods: The PCSK9 gene of the huh-7 hepatocellular carcinoma cells was knocked out by a strategy involving the introduction of a stop codon. The basic group editors of Td-CGBE-NG and AncBE4max were constructed, and the recombinant plasmids of sg386 and sg555 were generated. Co-transfection of Td-CGBE-NG and sg386, or AncBE4max and sg555, was conducted to the huh-7 cells to induce the conversion of c.1447C>G and c.1953C>T, thereby introducing the stop codons S386X (TGA) and Q555X (TAG) at the two positions. The editing efficiency was validated by the sanger sequencing and T-vector cloning. The changes of PCSK9 mRNA and protein expression levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting. Results: The results of the sanger sequencing and T-vector cloning showed that the editing efficiencies of Td-CGBE-NG and AncBE4max were c.1447C>G 33% and c.1953C>T 25%. RT-qPCR analysis revealed the reduction of PCSK9 mRNA expression by Td-CGBE-NG (t=17.29, P＜0.0001). Western blotting confirmed protein expression levels in both groups of huh7 cells had decreased significantly （AncBE4max:t=5.57,P＜0.01；Td-CGBE-NG:t=4.912, P＜0.01）. Conclusion: Td-CGBE-NG can knockout the PCSK9 gene of the huh-7 hepatocellular carcinoma cells effectively, which leading to the inhibition of the gene mRNA and protein expressions. These findings lay a foundation for the future application of Td-CGBE-NG.