Abstark: Telah dilakukan pengembangan terhadap buku ajar kimia pada materi asam, basa, dan garam dengan pendekatan konstruktivistik dan multirepresentasi kelas VII SMP yang bertujuan untuk mengetahui kelayakan dan keterbacaan buku ajar yang dikembangkan. Bentuk penelitian yang digunakan adalah penelitian dan pengembangan yang telah dimodifikasi. Subjek dalam penelitian ini adalah buku ajar. Hasil penilaian para ahli terhadap buku ajar yang dikembangkan diperoleh persentase kelayakan sebesar 88.395% (sangat tinggi) yang meliputi kelayakan isi, kelayakan kebahasaan, kelayakan penyajian, dan kelayakan kegrafikan berturut-turut sebesar 89%, 81,25%, 88,33%, dan 95% dengan kategori sangat tinggi. Hasil keterbacaan buku ajar memiliki persentase sebesar 89,13% dengan kategori sangat tinggi yang menunjukkan bahwa isi buku ajar mudah dipahami dan tampilan buku ajar menarik, sehingga baik untuk digunakan sebagai bahan ajar. Kata kunci: buku ajar, multirepresentasi, konstruktivistik Abstract: The development has been done toward the chemistry textbook on the acids, bases, and salts material with constructivist and multiple-representation approach of Grade VII which purposed to know the eligibility and legibility of the textbook developed. The form of this research is the research and development that has been modified. The subjects in this research is the textbook. Based on the expert judgement of the textbook developed the percentage of eligibility is gained about 88.395% (very high) which consist of the contents eligibility, the language eligibility, the presentation eligibility, and the graphic eligibility consecutive are 89%, 81.25%, 88.33%, and 95% with very high score category. The result of the textbook legibility has a percentage about 89.13% with very high category which indicates that the contents of textbook are easy to comprehend and it has attractive packaging, so it is good to use as teaching materials. Keywords: textbook, multiple-representaition, constructivist