Peri-implantitis is the inflammation of the hard and soft tissues around the implant, which is often clinically manifested as gingival or periodontal mucosa congestion, swelling, pus overflow; deep periodontal pockets or bone pockets are formed around the implant; implant loosening reaches or exceeds 1 degree; and X-rays show translucent shadows around the neck or body of the implant. Peri-implantitis is a key factor affecting the success rate of oral implant restorations, therefore, it is essential to prevent the occurrence of peri-implantitis. According to our clinical experience, the following points are important factors in the prevention of peri-implantitis: 1. Ask the patient carefully about his/her medical history before the surgery, and ask him/her to quit smoking if he/she smokes excessively, otherwise, he/she should carefully consider whether to implant. 2. Correct the patient’s habit of chewing on one side of the mouth. 3, For patients with nocturnal abrasion, it should be a relative contraindication to implantation, and if necessary, the patient should be allowed to wear a fitting cushion while sleeping, so as to guard against overloading of the implant. 4. Patients are required to maintain good oral hygiene, and patients with periodontitis should be treated by periodontist on the basis of strict selection of implant timing and indications. Unless there are strong clinical indications, implant restoration of posterior teeth should avoid immediate weight bearing, especially avoid premature weight bearing. 6, regular cleaning can prevent plaque aggregation, generally review and follow up once in 3-4 months interval, use carbon fiber head cleaning to prevent implant surface damage. 7, found that the implant local mucosal congestion, gingival swelling, should be taken in a timely manner progressive interception supportive therapy to block the development of peri-implantitis.