Objective The aim of this study was to observe the change of the prevalence of five- year- old children′ s dental caries for 10 years in Shanghai and to establish a related policy to provide a basis for the government. Methods The sampling method was multi- stage, stratified, adqulis capacity and whole flock in this study. The method of third national survey for oral health was used. The data of prevalence of dental caries, dmft and relative component were collected and were compared with the data of the second survey in 1995. Results The prevalence of dental caries, dmft, caries filling constitutent ratio of 5- year- old children in 2005 was 71.74%, 4.17, 7.70%, respectively, and denscend 6.54%, 0.59, 1.12% compare with the data in 1995. There was significant difference between them（P
