Oral health survey is a cross-sectional survey, which collects data such as frequency, epidemic intensity, distribution and epidemic law of oral diseases in a specific period. To understand the oral health status of a certain population; Master the epidemic characteristics of oral diseases; To reveal the factors affecting the occurrence of oral diseases and find the epidemic trend of oral diseases, so as to provide scientific basis for further oral health epidemiological research and oral health care work planning. The most commonly used method of status survey is questionnaire survey.