Liver cancer, such as secondary liver cancer and primary liver cancer, can be detected by abdominal ultrasound, but tiny liver cancer is easy to be missed during ultrasound examination. 1. Secondary liver cancer: secondary liver cancer is mainly caused by malignant tumor metastasis from other parts of the body to the liver. During ultrasound examination, single or multiple nodules or masses can be found in the liver, and the echoes of liver cancer foci can be hypoechoic or weakly echogenic, mixed echoes, accompanied by hypoechoic halo in the periphery, and obvious blood flow signals in the periphery and tissues. 2. Primary hepatocellular carcinoma: primary hepatocellular carcinoma often has the history of hepatitis or cirrhosis. Color ultrasound examination of the abdomen can find strongly echogenic, hypoechogenic or mixed echogenic nodules in the liver, and the nodules can be single or multiple. Multiple nodules may fuse to form a giant hepatocellular carcinoma. The border around the nodule is unclear, the shape is irregular, and there are obvious blood flow signals in the periphery and the cancerous foci. 3. Microscopic hepatocellular carcinoma: microscopic hepatocellular carcinoma refers to hepatocellular carcinoma with a diameter of ≤2cm, which can be easily neglected or missed during abdominal ultrasound because of its small size. When liver cancer is suspected by abdominal color ultrasound, it needs to be further diagnosed by MRI, enhanced CT, liver puncture and other examinations to confirm the specific degree and be treated in time.