A fat tongue can be caused by physiologic or pathologic factors. Common pathologic factors include tongue vascular malformation, tongue hemangioma, tongue trauma, tongue cancer and so on. 1. Physiological factors: some people are born with a large tongue and usually have no subjective symptoms. Due to the hypertrophy of the tongue, there are often teeth marks on the tongue, and traumatic ulcers often occur due to bites, which usually do not need special treatment. 2. Tongue vascular malformation: including venous malformation of the tongue, arteriovenous malformation, lymphatic malformation, etc., usually with the growth of the patient’s body in the same proportion to the growth of the tongue, resulting in the phenomenon of the tongue fat and thick, usually benign lesions. If the deformity is large, the shape of the tongue can be modified through surgery to reduce the size of the tongue. 3. Tongue hemangioma: there are a lot of hyperplasia of active vascular endothelial cells in hemangioma, which causes the gathering of mast cells, resulting in the hypertrophy of the tongue, and it can also be treated by surgery. 4. Tongue trauma: trauma can cause tongue tissue damage, causing blood vessel rupture, leading to blood accumulation in the tongue, which in turn causes limited swelling of tongue tissue, resulting in tongue enlargement and thickening. 5. Tongue cancer: it will lead to proliferation and infiltration of tumor tissues in the tongue, which will cause tongue enlargement and hypertrophy. In a word, it is recommended to go to the hospital for timely diagnosis and targeted treatment for the phenomenon of fat and thick tongue.