An epidemiological study of dental caries amongst preschoolers (aged between 4 and 6 years) from the city of Alicante has been carried out. The influence of the socioeconomic class as well as higienic and diet habits on the appearance dental caries of deciduous teeth has been evaluated. From a total population 7,289 preschoolers, a representative sample of 1,292 children was obtained by the sampling process of a stratified randomization. A statistical significant association was found between socioeconomic class and dental caries (p less than or equal to 0.05), being the lower classes the more prone to dental caries. Higienic habits of the examined children were clearly inadequate; 75.62% of preschoolers showing dental plaque. There was a statistical significant relationship between dental plaque and caries (p less than or equal to 0.05). The ingestion of candies has been shown to be also related with dental caries. Those children who never eat candies showed a prevalence of dental caries of 30.84%, whereas the prevalence increased up to 44% in cases of frequent ingestion of sugared food.