The causes of tongue cracks are physiological causes such as vitamin deficiency and pathological causes such as congenital fissured tongue and salivary gland diseases. 1. Physiological causes: when the lack of vitamins or insufficient intake of vitamins, such as vitamin B, makes the mucous membrane dry, rough, atrophy, so there will be the symptoms of cracked tongue; when the oral hygiene for a long time is poor, a large number of food residues stay in the oral cavity, so that the oral mucous membrane is irritated, atrophy, caused by cracked tongue. 2. Pathological reasons: when patients suffer from congenital cleft tongue caused by autosomal abnormality, the tongue mucosa or muscle atrophy, the symptoms of tongue cracks can appear; when suffering from salivary gland inflammation or salivary gland cysts and stones, the gland gland ducts are blocked, and salivary secretion obstacles lead to insufficient salivary secretion, resulting in dryness of the tongue, atrophy, and thus tongue atrophy will occur. When the clinical manifestation of cracked tongue occurs, you should go to the hospital for further examination and treatment under the guidance of professional doctors.