The two main components are serum alpha-fetoprotein (AFP) and liver ultrasonography. For men ≥ 35 years of age, with hepatitis B and/or C virus infection, and at high risk for alcoholism, screening is generally performed at 6-month intervals. For AFP > 400 μg/L without liver occupancy on ultrasound, care should be taken to exclude pregnancy, active liver disease, and tumors of embryonic origin in the gonads; if this can be ruled out, CT and/or MRI should be performed. If AFP is elevated but not at the diagnostic level, in addition to the above-mentioned conditions that may cause increased AFP should be excluded, the dynamic changes in AFP should be closely tracked, the interval between ultrasound examinations should be shortened to 1~2 months, and CT and/or MRI examinations should be performed when needed. If liver cancer is highly suspected, DSA hepatic artery iodine oil angiography is recommended.