In recent years, the CRISPR/Cas9 system has become a rapidly advancing gene editing technology with significant advantages in various fields, particularly biomedicine. Liver cancer is a severe malignancy that threatens human health and is primarily treated with surgery, radiotherapy, and chemotherapy. However, surgery may not be suitable for advanced cases of liver cancer with distant metastases. Moreover, radiotherapy and chemotherapy have low specificity and numerous side effects that limit their effectiveness; therefore, more effective and safer treatments are required. With the advancement of the biomolecular mechanism of cancer, CRISPR/Cas9 gene editing technology has been widely used in the study of liver cancer to gain insights into gene functions, establish tumor models, screen tumor phenotype-related genes, and perform gene therapy. This review outlines the research progress of CRISPR/Cas9 gene editing technology in the treatment of liver cancer and provides a relevant theoretical basis for its research and application in the treatment of liver cancer.