Small hepatocellular carcinoma (SHC) currently has no unified standard internationally, most scholars define SHC as lesion diameter <5cm, and also <3cm. In 1983, SHC was defined as a lesion <2cm in the clinical and pathological study specifications for primary liver cancer published by the Japanese Liver Cancer Research Group. With the continuous development of diagnostic imaging technology, the improvement of medical imaging detection level, the application of spiral CT, sixteen-row CT, MR, Pet, etc., the detection of SHC is significantly more than before, and even SHC of 1cm in diameter is not difficult to detect, so more and more small hepatocellular carcinomas are detected clinically. SHC is a single nodular type with swelling growth, clearly demarcated from surrounding liver tissues, with more than 65% having intact fibrous envelope, and few satellite nodes or metastases in liver tissues beyond 1.5 cm from the tumor edge, with long natural survival. Other treatments such as local injection of anhydrous alcohol (Peit), radiofrequency (RF), interventional embolization (TACE), radiotherapy (r-knife, X-knife) and freezing (argon-helium knife) are not suitable for the treatment of SHC, and should not be used as the first choice for SHC, but only for those who are not suitable for surgical treatment. The lesion located at the edge of liver can be wedge-shaped or partial hepatectomy, and the tumor in the center of liver can be shuttle-shaped resection or lipectomy, and the tumor near the hepatic portal area or hepatic vein can be resected radically by enucleation. For slightly larger tumors (3cm-5cm) or 2-3 small lesions scattered in one segment or lobe of the liver, segmental or lobectomy can be performed. The key to surgical resection of SHC is the preoperative intraoperative localization. Sometimes, for microscopic lesions deeply buried in the liver parenchyma with severe hepatic sclerosis, if the lesions cannot be detected by manual touch during surgery, it is difficult to resect the lesions. The distance between the tumor and the liver surface can be measured for surgical resection. For tiny lesions that can be detected by preoperative ultrasound and CT but cannot be reached intraoperatively, intraoperative ultrasound must be applied to carefully explore the liver segment where the tumor is located, and after the lesion is found, the location and depth are fixed by needle puncture, and the liver surface is cut along the needle path until the tumor is removed. Intraoperative ultrasound is more accurate than preoperative CT and intraoperative exploration.