Objective: The purpose of this study was to investigate the moderate effect of the physical environmental-level between infant teachers' positive play beliefs and teacher-infant interaction. Methods: The subjects of this study were 483 teachers in charge of oneyear- old and two-year-old infants in child care centers located in metropolitan areas. The data were collected by asking the teachers to respond to a questionnaire and the data collected were analyzed through correlation and hierarchical multi- regression analysis. Results: First, the positive play beliefs of the infant teacher, the physical environment level, and the teacher-infant interaction showed significant proportional correlations. Second, the physical environment level moderated the influence of the teacher's positive play beliefs on teacher-infant interaction. In particular, results showed that functional interior space configuration, outdoor playground composition and facilities among the sub-variables of the physical environment level had a moderating effect. Conclusion/Implications: The results of this study show that teachers with positive play beliefs have positive teacher-infant interaction when there is sufficient space available for infants and teachers. This indicates that the human and physical environments of child care centers can promote teacherchild interaction.