<pre><strong>Abstract:</strong> The purpose of this development research is to produce textbooks based on local content in Kabupaten Tulungagung for grade IV Primary School. Textbooks based on local content can be used as one learning resource in learning. The textbook product is developed based on the steps of the 4-D development model. Validation and test results that have been done, obtained data that is (a) the validation of the student's book reached a percentage of 85.34% with criteria is very valid; (b) the result of the attractiveness test on the student's book reaches 89.44% percentage with very interesting criteria; (c) the results of the practicality test students and teachers reached a percentage of 87.84% with very practical criteria; (d) the effectiveness test results that the learning outcomes have improved by comparing pretest and posttest results. </pre><pre><strong>Abstrak:</strong><em> </em>Penelitian pengembangan bertujuan untuk menghasilkan buku ajar berbasis Muatan lokal di Kabupaten Tulungagung untuk kelas IV Sekolah Dasar. Buku ajar berbasis muatan lokal dapat dijadikan salah satu sumber belajar dalam pembelajaran. Produk buku ajar dilaksanakan dengan langkah-langkah model pengembangan 4-D. Hasil validasi dan uji coba yang telah dilakukan, diperoleh data yakni (a) hasil validasi terhadap buku siswa mencapai persentase 85.34% dengan kriteria sangat valid; (b) hasil uji kemenarikan terhadap buku siswa mencapai persentase 89,44% dengan kriteria sangat menarik; (c) hasil uji kepraktisan siswa dan guru mencapai persentase sebesar 87.84% dengan kriteria sangat praktis; (d) hasil uji efektivitas bahwa hasil belajar mengalami peningkatan dengan membandingkan hasil <em>pretest</em> dan <em>posttest</em>.</pre>