The appearance of a nodule with a blister inside the mouth may be caused by herpes virus infection, oral ulcers, mucous gland cysts, etc. It can be treated by oral antiviral drugs, antiseptic and anti-inflammatory drugs, and cyst removal surgery. 1. Herpes virus infection: When herpes virus invades the oral mucosa and infects it, it may cause a nodule with blisters to appear in the patient’s mouth. It can be treated by oral antiviral drugs, such as acyclovir tablets, ribavirin tablets, etc. Caution should be exercised in patients who are allergic to the drug ingredients or have abnormal liver function. 2. Oral ulcers: oral ulcers occur in the oral mucosa, ulcerative injury disease, oral ulcers patients may appear in the oral cavity with blisters nodules phenomenon. Can be treated by oral antiseptic and anti-inflammatory drugs, such as roxithromycin capsules, metronidazole tablets, etc., allergic to drug components, pregnant women, breastfeeding patients with caution. 3. Mucous gland cysts: Mucous gland cysts are usually caused by the blockage of the salivary gland excretory ducts, saliva can not be discharged normally, so that the patient’s mouth with blisters appear in the nodules. It can be treated by cystectomy surgery, and after the surgery, patients should pay attention to regular checkups and eat a light diet. When a nodule with blisters appears in the mouth, it is recommended to consult a doctor in time to find out the cause of the disease and take appropriate treatment, such as medication should follow the doctor’s instructions, not to use medication privately.