Most of the hepatitis B patients in China are infected since childhood, and some of them have no accompanying symptoms, but are in a long-term viral activity state, which can easily evolve into cirrhosis and further malignant transformation into hepatocellular carcinoma. In clinical work, due to the insidious nature of hepatocellular carcinoma and the strong compensatory capacity of the liver, patients with early cirrhosis or early hepatocellular carcinoma often do not have complaints of discomfort and need to be detected during screening of high-risk groups and physical examination of middle-aged and elderly people. Among cirrhotic patients, it is even more difficult to distinguish early stage liver cancer nodules from cirrhotic nodules, which often leads to patients missing the opportunity of treatment and allowing the tumor to develop, which is ultimately difficult to cure. Therefore, early detection and early definite diagnosis are crucial in patients with chronic hepatitis B cirrhosis. The definition of small hepatocellular carcinoma by the Chinese Hepatocellular Carcinoma Pathology Collaborative Group is: the maximum diameter of a single carcinoma nodule should not exceed 3cm, and the number of multiple carcinoma nodules should not exceed two, and the sum of their maximum diameters should be less than 3cm. For early detection of small hepatocellular carcinoma, AFP test, which is simple, easy to perform and highly sensitive, is still preferred. Since chronic hepatitis and cirrhosis have a certain degree of hepatocyte regeneration and can have the potential to synthesize AFP at a certain stage of hepatocyte development, some patients can have elevated AFP, mostly in patients with active hepatitis or cirrhosis, but this type of elevated AFP often has the following characteristics: 1. most of HBV-DNA is positive and most of liver functions are abnormal, especially serum transaminases The magnitude of elevation is mostly below 200ng/mL; 3. The change of AFP is often positively correlated with the change of ALT, and the AFP value can drop to normal with the stabilization of the disease. If AFP is persistently positive or >500 ng/mL and gradually increases with time, and the dynamic curves of AFP and ALT are separated, we should be highly alert to the occurrence of liver cancer. Secondly, ultrasound imaging is a simple and reliable diagnostic imaging method for hepatocellular carcinoma, which can detect cases with negative AFP or low AFP concentration. Small hepatocellular carcinoma largely reflects the early stage of the tumor. Shen et al. used ultrasound imaging to determine the growth rate of hepatocytes and found that it took 9.8 months to 10.9 years for hepatocellular carcinoma to grow to the size of 10 cm from its onset. It was inferred that a rapidly growing 1 cm liver cancer takes at least 4.6 months to grow to 3 cm, therefore, examinations at intervals of 4 to 5 months can detect liver cancer below 3 cm. Therefore, regular checkups in high-risk groups are the basis for obtaining good treatment. If suspicious liver nodules are detected by BUS, further spiral CT examination is needed. To distinguish cirrhosis from early liver cancer, plain scan and dynamic three-phase contrast enhancement examination, including arterial phase, portal phase and delayed phase, are usually performed. Most small hepatocellular carcinomas can be seen in the arterial phase, and a few hepatocellular carcinomas with less blood supply do not have obvious arterial phase enhancement. The detection rate of small hepatocellular carcinoma less than 1 cm in diameter is about 20%, between 1 and 2 cm in diameter is about 75%, between 2 and 3 cm is about 85%, and above 3 cm is 100%. When CT is still unable to confirm the diagnosis, MRI can be combined with plain scan and dynamic enhancement, with plain scan including conventional T1 and T2 and their fat suppression sequences, and dynamic enhancement similar to CT enhancement, with arterial, portal and equilibrium scans, using the conventional extravascular gap contrast agent Gd-DTPA. A few lesions show equal or slightly high signal on T1WI and slightly high signal on T2WI. The signal in some lesions may be inhomogeneous, which may be due to the iron content in the nodules, and small hepatocellular carcinoma can show more obvious enhancement in the arterial phase of dynamic enhancement scan. Combined with the patient’s medical history and all the ancillary examinations, the diagnosis can still generally capture small hepatocellular carcinoma from cirrhotic nodules and take further treatments as early as possible, thus obtaining good treatment results.