Penelitian ini bertujuan untuk mengembangkan media pembelajaran Big Book yang digunakan guru dalam pembelajaran membaca awal di TK ABA Al-Hikmah Kretek Bantul Yogyakarta, serta menilai kelayakan media dan materi yang dihasilkan. Penelitian ini menggunakan metode penelitian dan pengembangan (Research and Development), yang dilaksanakan melalui empat tahap utama, yaitu define, design, develop, dan disseminate. Analisis data dilakukan dengan uji Paired Sample t-test untuk mengukur efektivitas media terhadap kemampuan membaca awal anak. Hasil penelitian menunjukkan bahwa media pembelajaran yang semula digunakan guru berupa bahan ajar cetak sederhana dan kartu huruf. Media Big Book yang dikembangkan menampilkan gambar dan teks bertema pengenalan anggota keluarga, benda di lingkungan sekitar, nama buah dan sayuran, serta hewan. Hasil validasi menunjukkan bahwa media Big Book berada dalam kategori sangat layak. Selain itu, uji efektivitas menunjukkan bahwa media tersebut berpengaruh signifikan terhadap peningkatan kemampuan membaca awal anak usia dini (p = 0,000; p < 0,05). Design and feasibility testing of big book media as a tool to stimulate early reading skills in kindergarten Abstract: This study aims to develop Big Book learning media for teaching early reading skills in TK ABA Al-Hikmah Kretek Bantul, Yogyakarta, and to evaluate the feasibility of the developed media and its content. The research employed a Research and Development (R&D) design, implemented through four main stages: define, design, develop, and disseminate. Data were analyzed using the Paired Sample t-test to assess the effectiveness of the media on children’s early reading skills. The findings indicate that the learning materials previously used by teachers consisted mainly of printed materials and letter cards. The developed Big Book incorporates illustrated and thematic content introducing family members, everyday objects, fruits and vegetables, and animals. The validation results show that the Big Book media is categorized as highly feasible. Furthermore, the effectiveness test reveals a significant improvement in early reading skills among kindergarten students after using the Big Book (p = 0.000; p < 0.05). This suggests that Big Book learning media can serve as an effective and engaging tool for stimulating early reading development in early childhood education settings.