The precise anatomical division of liver segments is the foundation of liver surgery, while the anatomical division of the S9 segment of liver is a further precise division of the caudate lobe of the liver. This article retrospectively analyzed and summarized the precise minimally invasive ablation and follow-up results of four representative lesions of the S9 segment of liver, including primary liver cancer, recurrent liver cancer, metastatic liver cancer, and focal liver hyperplasia, treated at Affiliated Dongguan Hospital of Southern Medical University. The aim of this study is to explore the minimally invasive ablation effect of lesions located at the S9 segment of liver under CT guidance.