Thyroid low density foci are considered to be caused by benign thyroid lesions, hyperthyroidism or hypothyroidism, thyroid cancer and other diseases, and need to be targeted treatment under the guidance of the doctor, such as regular review, surgical treatment, medication and so on. Thyroid hypodensity foci is a diagnosis of color ultrasound, indicating that the density of the shadow is low, and further refinement of the thyroid function test; if it is asymptomatic and normal thyroid function of benign thyroid hypodensity foci can be regularly reviewed, without special treatment. If it is associated with hyperthyroidism, patients need to take antithyroid drugs, such as methimazole, propoxythiazole, etc.; if it is associated with hypothyroidism, patients need to take levothyroxine sodium tablets. If thyroid cancer causes low density foci of the thyroid gland, surgical resection should be considered. Patients with hypodense thyroid foci are advised to go to the hospital for further clarification of the cause of the disease and actively cooperate with the doctor for treatment.