Primary malignant lymphoma of the liver is a rare primary malignant tumor of the liver, mostly diffuse large B-cell lymphoma. It has no extrahepatic invasion or enlarged lymph nodes in the early stages of the disease and is most commonly seen in middle-aged men, often with a background of immunosuppressive therapy, organ transplantation, or AIDS. Pathologically, tumor cells may grow nodularly or diffusely, and hepatic structures may be destroyed or preserved. Imaging examination shows that hepatic lymphoma manifests as hypoechoic lesions with clear or blurred borders on ultrasound; CT is hypointense on plain scan, and mild-to-moderate delayed enhancement on enhancement scan; MRI manifests long T1 and long T2 signals, with no obvious enhancement in arterial phase and mild-to-moderate enhancement in portal phase on enhancement scan. The diagnosis relies on pathological examination, immunohistochemistry, and other auxiliary diagnosis.