The purpose of this study was to examine the awareness of daycare teachers on SIDS(sudden infant death syndrome) and their preventive efforts of the syndrome in an attempt to suggest efficient preventive measures. The subjects in this study were 395 teachers in daycare centers located in Seoul. A survey was conducted by using questionnaires that this researcher prepared by modifying the SIDS-preventive guidelines provided by the AAP of the United States and the Ministry of Health & Welfare. As for data analysis, descriptive statistics analysis were carried out. The major findings of the study were as follows: First, daycare teachers were less anxious of the syndromeabout the possible occurrence of the syndrome. The daycare teachers thought that they would feel guilty and be skeptical in case of the occurrence of the syndrome, and both of them were greatly worried about subsequent legal responsibility and economic compensation. They pointed out the health status of infants as the most common cause of the syndrome, but they didn't think that sleeping posture or sleeping environments might be the cause. Second, the daycare centers didn't make use of subsidiary lighting or a brightness regulator a lot to prevent SIDS, and they didn't perform smoking-cessation publicity activities often, either, which was one of preventive measures. Moreover, 42.78 percent of the daycare teachers didn't receive any safety education related to SIDS. The daycare teachers better manage the health of infants. Third, the daycare teachers got a mean of 4.14 in SIDS-preventive childcare, which was a high score. Specifically, they scored high in health care(4.42), management of temperature and air(4.34) and lactation guidance(4.42), but they lagged behind in terms of sleeping guidance(3.88) and sleeping environments management(3.95). In particular, they scored lowest in the use of toy teats(2.81) and the use of lighting in a naptime(3.10). 71.0 percent of the daycare teachers had infants sleep on their face or on their side, which were reported to increase the incidence of SIDS. Given the findings of the study, more intensive safety education should be provided for daycare center directors and teachers to learn about correct sleeping posture and sleeping environments to ensure the successful prevention of SIDS. In addition, detailed safety criteria should be laid out, and sustained research efforts should be directed into SIDS. Finally, the government should offer institutional and financial assistance for daycare centers.