The main purposes of this research were to investigate factors for the development of basic Dharma traits (BDT) in preschool children and to promote the BDT which is one of a number of identified topics concerning ethics and morality targeted for urgent presentation to children and youth in Thailand. The study was conducted in two phases using kindergarten students aged 5 and 6. In Phase 1, teachers evaluated the BDT in 1,088 preschool children throughout Thailand using cluster sampling. The confirmatory factor analysis found that the preschool children showed BDT in eight areas of Diligence, Saving, Honesty, Discipline, Politeness, Cleanliness, Unity, and Kindness. Most of the preschool children could express examples of each area by themselves or with the assistance of teachers or friends. In Phase 2, a model for promoting the BDT of preschool children was developed through learning activities using sets of fables. These learning activities comprised fable books, storytelling activities, and supplementary Dharma activities and were used by the teachers with 326 students selected from the sample of Phase 1 by purposive sampling. The results showed that the model for promoting the BDT could obviously promote higher scores both in general and for all the specific areas.