Diffuse thyroid lesions are a symptomatic manifestation of thyroid disease. It can be manifested by ultrasonography. Diffuse thyroid lesions are commonly seen in nodular goiter, thyroid cancer, Hashimoto’s thyroiditis, hyperthyroidism, etc. Nodular goiter usually does not cause any obvious discomfort when the nodules are small, but when the nodules are large, sometimes the thyroid gland may become enlarged, which may cause pain, difficulty in breathing, hoarseness, and sometimes even bleeding in the throat. 2. When thyroid cancer is detected in the thyroid gland during ultrasound examination, the echogenicity of the lump is uneven, the surface is uneven and the texture looks hard. It is also accompanied by hoarseness of the voice and may affect breathing when the mass is large. 3. Ultrasound examination of Hashimoto’s thyroiditis may reveal symmetrical and diffuse enlargement of both lobes of the thyroid gland, with uneven surface, irregular shape, uneven echogenicity in the gland, and sometimes thickening of the isthmus. 4. Hyperthyroidism can be seen as rich blood flow signals during ultrasound examination, mostly in the form of pyrosis, and sometimes there is also echogenic inhomogeneity in the gland. During ultrasound examination, the above symptoms need to be further examined to avoid delaying the cause of the disease.