This study explores the key challenges encountered in the implementation of extensive reading in the Thai context. The samples were 400 Thai students and teachers who were already familiar with the concept of ER. The participants' opinions, thoughts, and beliefs about the implementation of ER were also gathered through surveys and semi-structured interviews. The results reveal that these challenges include teachers' beliefs about ER; insufficient support from schools and educational authorities; teachers' workload and lack of training; and students' motivation and reading habits. Overcoming these challenges requires collaborative efforts between educational institutions, administrators, teachers, and students to provide adequate resources, training, and a supportive environment to promote a reading culture in the EFL classroom in Thailand. Extensive reading programs (ERP) can be effectively implemented in Thailand by recognizing and resolving these issues, which will improve language learning outcomes and a lifelong motivation for reading among students.