Purpose: This study was conducted to develop and implement a case-based small group learning program on the care of children with infectious disease, and to examine its effects on knowledge, attitude and preventive practice behaviors of daycare center teachers compared to a control group. Methods: Based on the need assessment, the case-based learning program for the management of infectious children was developed. For this quasi-experimental study, 69 teachers were recruited from 14 child daycare centers in a city located in J province. Thirty four teachers were assigned to experimental group and participated in the case-based small group learning once a week for 5 weeks. Data were analyzed using the SPSS 18.0 program to perform ${chi}^2$-test and t-tests. Analysis of covariance was used to treat the covariate of the number of assigned children between experimental and control groups. Results: The experimental group showed significantly higher posttest scores in knowledge, attitude and preventive practice behaviors than those of control group (p<.001). Conclusion: These findings indicate that case-based small group learning is an effective educational strategy for daycare center teachers to learn infection management through the emphasis of self-reflection and discussion.