A thick white tongue and a fat tongue with teeth marks are commonly seen in patients with chronic poor oral hygiene or gastrointestinal digestive disorders. Tongue moss is a Chinese medical term that actually consists of filiform papillae and fungiform papillae on the mucosa of the tongue. Filiform papillae and fungiform papillae are white conical projections formed by the keratinized epithelium of the tongue mucosa. The thickening of the tongue indicates poor oral hygiene, which can cause imbalance in the ratio of tongue mucosal flora and stimulate poor or slow keratinization of the filiform papillae and mycotic papillae of the tongue. Gastrointestinal digestive disorders can also cause reflux of gastric acid or esophageal gastric juice, and the imbalance of oral flora ratio indirectly leads to thick white tongue moss. Fat tongue with tooth marks is due to metabolic disorders leading to systemic edema, edema of the tongue, and the tongue pressing on the teeth to form the corresponding tooth marks.