Penelitian ini bertujuan untuk mendeskripsikan keefektifan pendekatan open-ended dan inkuiri terbimbing ditinjau dari kemampuan pemecahan masalah dan representasi multipel matematis. Peneli-tian ini juga mendeskripsikan perbedaan keefektifan pendekatan open-ended dan inkuiri terbimbing ditinjau dari kemampuan pemecahan masalah dan representasi multipel matematis. Jenis penelitian yang digunakan adalah penelitian eksperimen semu, yang terdiri atas dua kelompok eksperimen. Populasi dalam penelitian ini adalah seluruh siswa kelas VII SMP Negeri 2 Kota Ternate. Untuk menge-tahui keefektifan pendekatan open-ended dan inkuiri terbimbing pada variabel kemampuan pemecahan masalah dan representasi multipel matematis digunakan uji one samples t-test. Selanjutnya dilakukan uji Mancova untuk mengetahui perbedaan keefektifan antara kedua kelompok, dan dilanjutkan dengan uji lanjut yaitu uji Fisher Hayter untuk mengetahui pendekatan mana yang lebih efektif. Hasil peneli-tian menunjukkan bahwa pendekatan open-ended dan inkuiri terbimbing efektif ditinjau dari kemampuan pemecahan masalah dan representasi multipel matematis siswa. Selain itu, hasil penelitian me-nunjukan bahwa pembelajaran matematika dengan pendekatan open-ended tidak lebih efektif dari pendekatan inkuiri terbimbing ditinjau dari kemampuan pemecahan masalah matematis dan pende-katan open-ended lebih efektif dari pendekatan inkuiri terbimbing ditinjau dari kemampuan represen-tasi multipel matematis. Kata Kunci: pendekatan open-ended, pendekatan inkuiri terbimbing, kemampuan pemecahan masa-lah matematis, kemampuan representasi multipel matematis.   Open-Ended and Guided Inquiry Approach in Terms of Problem Solving and Multiple Representation Mathematics Abilities   Abstract This study aims to describe the effect of open-ended approach and guided inquiry approach in each term of student’s mathematics problem solvingand multiple representation mathematics abili-ties. This study is to describe a difference in the effectiveness of open-ended approach and guided inquiry approach in term of problem solvingand multiple representation mathematics abilities. This study is a quasi-experimental research study, using two experimental groups. The research population comprised all grade VII students of SMP Negeri 2 Ternate City. To find out the effectiveness of open-ended approach and guided inquiry approach in terms of variable mathematics problem solvingand multiple representation mathematics abilities one samples t-test was used, Mancova test to find out the difference in effectiveness between the two groups, and a post-hoc Fisher Hayter test to reveal which approach was more effective. The results of the study show that open-ended approach and guided inquiry approach is effective in terms of mathematics problem solvingand multiple representation mathematics abilities of the students. The results of the study also show that open-ended approach is not more effective than the guided inquiry approach in terms of students mathematics problem solvingabilities; and open-ended approach is more effective than the guided inquiry approach in terms of multiple representation mathematics abilities. Keywords: open-ended approach, guided inquiry approach, mathematics problem solvingabilities, multiple representation mathematics abilities.