Sublingual gland cyst is a common salivary gland cyst, which occurs in adolescents and can be clinically classified into three types: 1. Simple type: the most common, the cyst is located in the sublingual floor of the mouth area, the cyst is often light purple-blue, soft to the touch with a sense of fluctuation. The cyst may rupture due to eating, and may flow out thick and slightly yellow or egg white like liquid, and the cyst disappears temporarily. After a few days, it will grow again. 2.Oral shape: The cyst is mainly located in the submandibular area, and the swelling in the mouth is not obvious, but it may slightly increase when the head is lowered. 3.Dumbbell type: It is a mixture of the above two types, and the cyst can be palpated inside and outside the mouth. Since sublingual cysts often appear as “small abscesses” under the tongue or swelling in the submandibular area on one side, treatment is often delayed or treated as submandibular cysts (submandibular cysts are rare), so it is best to puncture first, and if yellow egg-white-like stretched fluid comes out, the diagnosis of this disease can be basically confirmed. The treatment for this disease is usually surgical, the affected sublingual gland can be removed, the surgery is small, if the cyst is not large, usually can be removed from the mouth, the face will not have an incision, and will not affect the function of saliva secretion.