Primary liver cancer can be differentiated and diagnosed from other diseases by laboratory tests and imaging examinations. The diagnostic criteria for primary liver cancer are: (1) two typical imaging (US, enhanced CT, MRI or selective hepatic arteriography) manifestations of hepatocellular carcinoma, with a lesion >2cm; (2) one typical imaging manifestation of hepatocellular carcinoma, with a lesion >2cm, and an AFP >400ng/mL; (3) a positive liver biopsy. Testing AFP and US screening every 6 to 12 months in high-risk groups (chronic hepatitis due to various causes, cirrhosis, and HBV or HCV-infected people >35 years old) can help in the early diagnosis of primary hepatocellular carcinoma. Primary liver cancer often needs to be differentiated from secondary liver cancer, cirrhosis, liver abscess and other diseases. 1. Secondary hepatocellular carcinoma: cancer foci originated from respiratory tract, gastrointestinal tract, genitourinary tract, breast, etc. often metastasize to liver, especially colorectal cancer, which is most common, showing multiple nodules, with clinical manifestations of primary cancer, and serum AFP test is usually negative. 2. Cirrhotic nodule: Enhanced CT/MRI shows arterial enhancement of the lesion, which is fast in and fast out, diagnosis of hepatocellular carcinoma is made; if there is no enhancement, cirrhotic nodule is considered; AFP＞400ng/mL is helpful for the diagnosis of hepatocellular carcinoma. 3.Liver abscess: clinical manifestations include fever, pain in liver area, obvious pressure pain, elevated white blood cell count and neutrophils.US examination can find liquid dark area of abscess. If necessary, diagnostic puncture or drug experimental treatment under ultrasound guidance is done to clarify the diagnosis. The presence of primary hepatocellular carcinoma is suspected, and active consultation and standardized treatment are recommended.