The quality of Executive Functions (EF) practicing of teachers supports children to learn and improve EF. EF development in children is a new topic in Thai education that has to be investigated. This study aims to investigate the relationship among knowledge, attitudes, and practicing of teachers’ executive functions (EF) in childcare centers. These relationships were examined in a Thai context (n = 100). A questionnaire survey was performed to canvas teachers’ knowledge, attitudes, and EF skills practicing. The data were analyzed using Spearman’s Rho correlation. The results demonstrated that the teachers understood the concept of EF, possessed positive attitudes toward promoting EF development, and regularly practiced activities for EF development in children (75.72%, 79.98%, and 77.21%, respectively). The results revealed that having sufficient knowledge and a positive attitude toward the EF have a positive relationship with practicing activities related to EF development. This study suggested that further knowledge should be provided in simple strategies that encourage a positive attitude towards exercising EF in children and allow teachers to plan EF activities in childcare centers on a daily basis.