FNH is a benign tumor of the liver of hepatocellular origin, which accounts for about 8% of primary tumors of the liver and ranks second only to hemangioma among benign tumors of the liver. The etiology of FNH is still unclear, and most scholars believe that it is a proliferative response of hepatocytes to local vascular abnormalities, rather than a true tumor. Some scholars believe that the occurrence of FNH may be related to inflammation, trauma or vascular malformation. This view is also supported by the thickened blood supply arteries found in 11 cases in our CT group. The use of contraceptives does not increase the incidence of FNH, but may promote the growth of FNH. Most patients with FNH have no clinical symptoms and are only found incidentally during physical examination or related tests. FNH is often misdiagnosed as primary hepatocellular carcinoma. The pathological features of FNH can be divided into two types: (1) Classic, also known as parenchymal or solid type, which is more common and has three typical features: abnormal nodular structure of hepatocytes, central stellate scar or curved thick-walled vessels and different degrees of small bile duct hyperplasia. (2) Atypical, accounting for about 19.7% of cases. Those with varying degrees of small bile duct hyperplasia and one of the two features of abnormal nodular structure of hepatocytes or curved thick-walled blood vessels, largely without central stellate scarring. They can be subdivided into 3 subtypes: vasodilated, adenomatous hyperplasia and atypical large cell type. To summarize our cases and review the literature, the main imaging examinations of FNH are ultrasound, CT, MRI, etc. The combined application of the above examinations can increase the diagnosis rate to 80%, which is about 90% in our cases. Color ultrasound can clearly show the structure and blood vessels in the mass, and together with angiography, can greatly improve the diagnosis rate. CT scan and enhancement can show the vascular characteristics and spoke-like structure of the mass. In our group, 76% of the patients had this typical presentation. MRI is considered to be one of the better methods to diagnose FNH, but only 21.4% of our group had a plain scan MRI with a low rate of central scarring, and it is sometimes difficult to differentiate FNH from hepatic adenoma or hepatocellular carcinoma, especially for lesions less than 3 cm in diameter. In most cases of classic FNH, CT or MRI has typical manifestations, so it is easy to make a correct diagnosis. In contrast, nearly 20% of classic FNH and almost all atypical FNH are difficult to diagnose by imaging alone due to the lack of a central scar. Note that fine needle aspiration biopsy carries the risk of bleeding and malignant tumor implantation. FNH is a benign tumor of the liver, no cancer is reported, and it rarely ruptures and bleeds, only 4 cases of rupture and bleeding have been reported. In a few cases, a small amount of bleeding was seen in the lesions, but the tumors were all intact and no signs of rupture were found. In our group, a small amount of bleeding was seen within the cut surface of the lesion in two cases. For asymptomatic FNH with a clear diagnosis and a small tumor, regular follow-up should be performed. If the mass is not enlarged or if the mass shrinks, observation can be continued. Patients with undiagnosable FNH or suspected hepatocellular carcinoma or hepatic adenoma should be operated aggressively. Pay attention to differentiate from highly differentiated hepatocellular liver cancer. The literature reports two cases in which CT, MRI and color ultrasound showed typical manifestations of FNH, and the preoperative diagnosis of FNH was confirmed, while the postoperative pathology was hepatocellular hepatocellular carcinoma. The surgical approach was local resection of the mass, lobectomy or segmental resection of the liver, with the former being the main approach. The resection included all of the tumor and part of the surrounding normal liver to avoid residual tumor tissue and recurrence. In this group, 15 cases of local resection of liver, 19 cases of left outer lobe resection of liver and 1 case of left hemicolectomy were performed, and all of them were cured after surgery. For small tumors and located in the liver parenchyma, since they are not easily detected by the naked eye and not easily palpable during surgery, intraoperative ultrasound should be prepared to determine the incision margin according to the localization. For large tumors that are difficult to be resected, the hepatic artery can be embolized or ligated first, and then “second stage resection” can be performed after the tumor shrinks. The prognosis of FNH is good, but follow up is important. If recurrence is found, reoperation is required. All of the cases in this group are still alive after surgery and no tumor recurrence has been found.