Mucous cysts of the salivary glands are common small salivary adenoma-like lesions that occur on the ventral side of the lower lip and tongue, and the most common treatment is surgery. Clinical manifestations: The submucosal glands are injured because the tongue movement is often injured by friction of the lower anterior teeth and by the conscious or unconscious action of biting the lower lip. The cyst is located in the submucosa, and the surface is only covered with a thin layer of mucosa, so it appears as a translucent, light blue blister, resembling a blister. Most of them are soybean to cherry size, soft and elastic in texture. The cysts are easily ruptured by bites and flow out clear egg-white like sticky liquid, and the cysts disappear. After the rupture heals, it is filled with mucus and forms cysts again. Repeated ruptures no longer have the clinical features of cysts, but show thicker white scar-like protrusions and reduced transparency of cysts. Treatment: 2% tincture of iodine 0.2~0.5ml can be injected into the cystic cavity after the cystic fluid has been extracted and left for 2~3 minutes, after the tincture of iodine has been extracted. The purpose is to destroy the epithelial cells so that they lose their secretory function and no longer form cysts. It can also be injected with 20% sodium chloride. However, the most commonly used treatment is still surgical excision.