The ultrasound features of malignant lymph nodes in the neck mainly include shape, border, lymphatic gate and blood flow distribution. 1. Shape: Normal lymph nodes are oval or kidney shaped, malignant lymph nodes are more, lose their normal shape and grow into round shape, the shape is a better indicator to identify malignant lymph nodes in the neck, but it is not absolute. 2. Boundary: malignant lymph nodes in the neck have irregular and sharp edges due to tumor invasion, abnormal lymph nodes and increased acoustic impedance of the surrounding tissues in the case of identified malignant lesions. 3. Lymphatic gate: malignant lymph nodes in the neck are mainly due to the disappearance of lymphatic gate as a result of tumor infiltration of normal lymph node tissue. 4. Blood flow distribution: malignant lymph nodes in the neck include metastatic and lymphoma, showing mixed or peripheral blood flow signals, if ultrasound suggests that the blood flow signals are strong, it indicates the possibility of malignant lymph nodes in the neck. The ultrasound characteristics of malignant lymph nodes in the neck also include size, lymph node echogenicity and other tests, and it is recommended that the patient seek medical attention in a timely manner and receive treatment immediately upon diagnosis.