Thyroid nodule with blood flow signal may be thyroid nodule with secretory function, thyroid cancer and other diseases. Thyroid nodules with secretory function have a better prognosis after standardized treatment and are not considered serious; thyroid cancer is more serious. Thyroid nodule with blood flow signal is a kind of manifestation under imaging examination, which indicates that the surrounding blood flow is more abundant, and there may be thyroid nodule with secretory function, thyroid cancer and other diseases. Thyroid nodules with secretory function will secrete thyroxine and lead to hyperthyroidism. Generally, the use of antithyroid drugs, such as propylthiouracil, etc., in accordance with the doctor’s instructions, the prognosis is better after standardized treatment and is generally not considered serious. Thyroid cancer is a kind of malignant tumor, so it is more serious, but the prognosis is relatively good among malignant tumors. In case of thyroid nodule with blood flow signal, it is recommended to go to the hospital as soon as possible and ask the doctor to make a judgment. After clear diagnosis, follow the doctor’s instructions to standardize the treatment.