Early diagnosis is crucial. Since the 1970s to 1980s, the early diagnosis of hepatocellular carcinoma has been greatly facilitated by the gradual popularization and widespread use of serum AFP, real-time ultrasound imaging and CT. As the early diagnosis rate has increased significantly, the surgical resection rate has increased and the prognosis has also improved significantly; therefore, the diagnosis of hepatocellular carcinoma, especially the early diagnosis, is the key to clinical treatment and prognosis. In terms of early diagnosis, full attention should be paid to the background of liver disease of patients. In China, 95% of patients with hepatocellular carcinoma have a background of hepatitis B virus (HBV) infection, 10% have a background of hepatitis C virus (HCV) infection, and some patients have overlapping HBV and HCV infection. Special attention should be paid to the following risk groups: middle-aged and elderly men with high HBV load, HCV-infected patients, patients with overlapping HBV and HCV infections, alcoholics, patients with combined diabetes mellitus, and patients with family history of liver cancer. After the age of 35-40 years, these people should be screened regularly every 6 months (including serum AFP test and liver ultrasound); when there is an elevated AFP or “occupying lesion” in the liver area, they should immediately enter the diagnostic process and be closely observed to make an early diagnosis.