With the development of science and technology, most common oral diseases can be prevented through oral health education and health care measures. In many advanced countries, due to the extensive implementation of various preventive measures, the prevalence of oral diseases has been significantly reduced, while in China, due to the economic level and people’s ideological understanding, the oral preventive health care in China is still in the primary stage. Preventive oral health care measures can greatly reduce the incidence and prevalence of common oral diseases and diseases, can save a lot of health resources, has a lot of advantages of low investment, quick results, reduce patient pain and economic burden. Promote the development of oral preventive health care, improve people’s awareness of oral health care is a top priority. For this reason, since 1989, China has designated September 20 each year as “National Dental Day”, the purpose is to carry out universal dental health promotion activities. Oral preventive health care has obvious preventive effect on the development of the following diseases: 1, dental caries (worm teeth). 2, periodontal disease (gingivitis, periodontitis, bleeding gums, bad breath, etc.). 3. Tooth and jaw malformation (uneven teeth, crowded teeth, “whistling teeth”, “envelope”, “bird’s mouth deformity”, etc.). 4. Temporomandibular joint disorders (joint popping, pain, strangulation, mouth opening restriction, etc.). 5. Precancerous lesions (mucosal leukoplakia, erythema, lichen planus, persistent oral ulcers, etc.), basal cell carcinoma of skin nevus origin, malignant melanoma, etc. Common oral preventive health care measures: 1. Brush teeth and rinse mouth regularly, take correct brushing method, floss correctly, clean teeth and visit dentist regularly (half year or a year); eat less food with high sucrose content and keep balanced nutrition; use fluoride toothpaste and medicated toothpaste; it can prevent the occurrence of dental caries and periodontal diseases. 2. Do the health care of pregnant women to reduce the congenital oral and maxillofacial deformities; adopt the correct feeding and sleeping posture of infants, ensure the comprehensive and balanced nutrition of infants and children, correct the partial eating habits of children and bad habits such as tongue spitting and pen biting, play the stimulating effect of chewing movement on jaw development, early treatment of dental caries, early loss of milk teeth, rickets and respiratory diseases is important to prevent the occurrence of dental and jaw deformities. 3.Avoid the habit of lateral chewing, correct the habit of grinding teeth at night and clenching teeth; avoid long-term excessive mental tension and keep a happy mood; correct the malformation of teeth and jaws as early as possible and keep the normal bite and jaw relationship can well protect the temporomandibular joint. 4.Eat less hammer, smoke less, drink less, eat less spicy and stimulating food; strengthen the intake of vitamins and mineral trace elements and maintain balanced nutrition; reduce the local stimulation of tooth tips and bad restorations, avoid scratching skin moles or sun exposure; all can reduce the occurrence of precancerous lesions and tumors.