Low-density shadow in the right lobe of the liver on CT examination, common diseases include right lobe cyst, right lobe hemangioma, right lobe tumor, etc. According to different diseases, the severity is also different. 1. Right lobe cyst of the liver: on CT image, it is mostly manifested as round or oval low-density shadow with clear boundary; after enhancement scanning, the lesion usually has no obvious enhancement, which is a common benign lesion, and no special treatment is needed in general. 2. Hemangioma of right lobe of liver: in CT scanning, it is characterized by round-like low-density shadow with clear boundary; in CT enhancement scanning, it is characterized by “fast in and slow out” of contrast agent. Early lesions are rapidly intensified and delayed lesions are filled with isodensity, which are benign lesions and need regular review to observe whether there is obvious growth of lesions, and interventional angioembolization can be carried out if there is obvious growth. 3. Right lobe of liver tumor: in CT scanning, the tumor is characterized by rounded low-density shadow with unclear boundary; in CT enhancement scanning, it is characterized by “fast in and fast out” of contrast agent, with rapid intensification of the lesion in early stage and rapid decrease of intensification of the lesion in delayed stage; it needs to actively cooperate with the doctor to carry out the treatment. CT examination of the right lobe of the liver hypodense shadow, the need for further examination in a timely manner, to identify the cause of the disease, timely cooperation with doctors for treatment, so as to avoid delaying the condition.