Objective: To assess risk factors of early childhood caries (ECC) in a community in Myanmar in order to tailor the content of an oral health promotion program for mother and child health clinics in that community. Methods: Information on nursing, dietary and toothbrushing habits was collected through a structured interview from 405 mothers with 18-30-month-old children in Daik-U, 87 miles north of the capital, Yangon. Caries in infant's teeth was scored according to the WHO criteria. Results: Of the 18-24-month-old children, 29.7% had caries and the mean dmft was 1.1±1.9. Of the 25-30-month-old children, 50.5% had caries and the mean dmft was 2.2±2.6. Of the 405 children, 340 were breastfed without bottle feeding and 99% of them shared the bed with their mother. Only a few children were purely bottle fed after the age of 12 months. In a multiple regression analysis with dmfs as dependent variable, gender, location of residence, fluoride content in drinking water, mother's education, father's occupation were not associated with ECC. In contrast, the total exposure time to breastfeeding and the habit of keeping mother's breast nipple in the infant's mouth during the night were strongly associated with ECC. Moreover, the consumption of supplementary food containing sucrose and rice that was pre-chewed by the mother was also strongly associated with ECC. Only a few mothers brushed the teeth of their infants before the age of 18 months. Conclusion: Prolonged and intensive breastfeeding, keeping mother's breast nipple in the mouth during the night and consumption of sucrose containing supplementary food and pre-chewed rice are risk factors for ECC. These risk factors as well as early toothbrushing with fluoride toothpaste should be emphasized in a program of oral health promotion for infants in this community. This study was supported by WHO Collaborating Centre, Nijmegen, The Netherlands.