With the development of society and the improvement of people’s living standards, people are paying more and more attention to oral health. As a large group of elderly people, their oral health has attracted even more attention. For elderly people, the main daily cavity problems related to aging are root surface caries, edentulous jaw and unhealthy mucosa and periodontal tissue. Caries is commonly known as “tooth decay”, which is mainly caused by decalcification of teeth caused by the decomposition of food and acid production by bacteria adhering to the tooth surface. The gap between teeth widens and the roots of teeth are exposed, thus causing the caries of the elderly with obvious characteristics. Firstly, the gender difference is significant, and the caries rate of elderly women is obviously higher than that of men, which may be related to the diet habits of women such as sweet food and snack food. Another characteristic is that root surface caries is obviously more than crown surface caries. Due to the good periodontal attachment, the root surface is less exposed and the caries mostly occurs in the crown part; while in the elderly, the root is exposed due to the ageing change mentioned above, plus the poor oral hygiene and the intake of sugar and sweet food, thus it is very easy to form root surface caries. Another important reason for root surface caries is that most of the elderly people wear dentures and if the oral hygiene is not good and the cleaning is poor, it will easily cause root surface caries. Then, how should the elderly people improve their oral health care ability to reduce the chance of caries? We think we should insist on the following points: 1. Learn the correct brushing method. The elderly should choose the health care toothbrush for the elderly or adults that meets the requirements of oral hygiene, and choose the fluoride toothpaste to prevent the root surface caries. When brushing teeth, it is best to use vertical brushing method with moderate strength and time around 3 minutes, too vigorous root brushing method is easy to cause tooth damage. 2, in addition to insist on brushing, cleaning the gap between the teeth is also very important. Because older people have wider gaps and loose teeth, brushing alone is not enough to keep them clean, so it is recommended to use a gap brush when available. If there is no gap brush or dental floss, you can use flat or wedge toothpick to slide slowly along the two touching surfaces of each tooth, don’t force too hard and too fast, this can help to clean the soft tartar and plaque on the adjacent surface of teeth and effectively prevent the occurrence of root surface caries. 3, also remind the elderly friends to pay attention to protect the abutment teeth, that is, the teeth used to support the dentures, these teeth are often neglected and not cleaned. Take out the dentures every day and after meals, and clean the abutment teeth carefully and meticulously. If the abutment teeth have disease should be promptly to the specialist hospital. 4.The key point is that you should make the habit of regular oral examination. The above knowledge about dental caries prevention and oral health care for the elderly, I hope it will be beneficial to the dental health of the elderly.