AbstrakPenelitian bertujuan menghasilkan bahan ajar berkarakteristik Problem Based Learning, mengkajikevalidan, keefektifan, serta kepraktisan bahan ajar berbasis Problem Based Learning. Jenis penelitianResearch and Development (R&D). Metode penelitian dari Sugiyono; analisis tahap potensi dan masalah,pengumpulan data, desain produk, validasi desain, revisi desain, uji coba produk, uji coba pemakaian danproduk akhir. Subjek penelitian adalah siswa dan guru kelas V SD Gugus Ki Hajar Dewantara Rembang.Teknik pengambilan sampel menggunakan teknik simple random sampling. Teknik pengumpulan datamenggunakan wawancara, tes, kuesioner, dan dokumentasi. Hasil penelitian menunjukkan; produk bahan ajaryang dikembangkan valid dan layak, persentase kelayakan isi 83,3% (layak), aspek kelayakan penyajian 87,5%(sangat layak), aspek kelayakan model Problem Based Learning 85,7% (sangat layak), aspek kelayakankegrafikan 87,5% (sangat layak), dan aspek kelayakan kebahasaan 80% (layak). Berdasarkan uji t dengan nilaisignifikansi 0.000 < 0,05 dan uji gain yang bernilai 0,42 dengan kategori sedang berarti bahan ajar efektifdigunakan. Bahan ajar berbasis Problem Based Learning praktis digunakan, persentase respon guru secaraklasikal 84,1% (positif), persentase respon siswa secara klasikal 86,8% (sangat positif). Simpulan penelitian,bahan ajar yang dikembangkan berkarakteristik Problem Based Learning, valid untuk digunakan, efektifmeningkatkan hasil belajar siswa dan praktis digunakan dalam pembelajaran. AbstractThis research aimed to produce learning material based on problem based learning, to know validity,effectiveness, and the eligibility of learning material. This research was Research and Development (R & D),used the model of Sugiyono which consist of potential and problem analysis, data collection, productdesigning, product validation, product revision, product testing, operational testing, and final product. Thesubject of this research were students and teachers of class V at SD Ki Hajar Dewantara Rembang cluster. Thesampling technique used simple random sampling. The data collection technique used interview, test,questionnaire and documentation. The result showed: the teaching material which developed was valid andproper, percentage of content eligibility was 83,3% (valid), serving eligibility was 87,5% (very valid),graphical eligibility was 87,5% (very valid), problem based learning model eligibility was 85,7% (very valid),and language eligibility was 80% (valid). Based on t-test significance value which was 0,000 < 0,05 and gaintest was 0,42 with medium criteria, material learning was effective. Material learning based on problem basedlearning was practical to be used, the classical percentage from teacher which was 84,1% (positive) andstudent’s response percentage which was 86,8% (very positive). The conclusion of this research were learningmaterial was developed based on problem based learning valid to be used, effective to improve learningoutcomes, and practice to be used in learning.