Developing executive functions (EF) is a crucial issue in early childhood development which is also important in 21st-century learning. EF guideline was developed by Permsubhirunya and co to provide a guide for teachers who seeks to develop learning activities that could improve executive functions in children under the age of 6. The purpose of the study was to investigate the effect of the utilization of the EF guideline on the development of early childhood teachers' abilities in designing learning experiences for EF development. The study was conducted with a qualitative approach. The participants were 65 teachers in public early childhood centers in Thailand. The participants were purposively selected using the criteria of their work status and experience. The instruments were the EF guideline, an evaluation form for learning management design ability and learning material selection, and an interview form. The data were analyzed using content analysis and thematic analysis. The results of the study were in the descriptive presentation. The findings could be summarized that the use of the EF guideline was beneficial in developing teachers' knowledge of the early childhood executive functions, abilities to design learning management, and ability in selecting or creating learning material. The findings also suggested that teachers perceived the EF guideline as potential learning material that help them make a connection between the plan, activities, and evaluation. Therefore, it also helped them control the process of learning management and contribute to a meaningful learning environment.