Purpose: The aim of the present study was to examine the prevalence, severity and association of developmental enamel defects (DED) and dental caries in a sample of 4- and 5-year-old children living in Jeddah, Saudi Arabia. Methods: A total of 510 children were examined in nursery schools using a penlight, a mouth mirror and a CPI probe. Dental defects were described using the modified DED index, the caries were described using the decayed, missing and filled teeth (DMFT) index. Results: The prevalence of DED of any type was 45.4%, with that of demarcated opacities being the highest, followed by hypoplasia. The most frequently affected teeth were maxillary anterior teeth, while the least affected teeth were mandibular incisors. The mean DMFT was 3.9. A positive association between DED and caries was observed. Conclusions: The prevalence of enamel defects and caries was high, as the enamel defects were strongly associated with caries; therefore, this association must be considered when focusing on the prevalence of caries in the Saudi community. Keywords: caries, developmental enamel defects, hypoplasia, opacities, primary dentition