This study aims to determine the effectiveness of the problem-posing type pre-solution posing model against students' mathematical problem-solving abilities. This type of research is an experimental study with a pre-test post-test control group design. The population in this study was 256 students grade VII one of Junior High School in Salatiga in the academic year 2018/2019 divided into 8 classes. Through the cluster random sampling technique, the VIIE class students were selected as the experimental class and the VIIH class students as the control class. The technique of collecting data on mathematical problem-solving ability through pre-test and post-test. The data analysis technique used the independent sample t-test on the N-Gain score. The results showed that the application of the problem-posing type pre-solution posing more effective against students' mathematical problem-solving abilities compared to students who received conventional learning.Penelitian ini bertujuan untuk mengetahui efektivitas model problem posing tipe pre-solution posing terhadap kemampuan pemecahan masalah matematik siswa. Jenis penelitian ini merupakan penelitian eksperimen dengan pretest-postest control group design. Populasi dalam penelitian ini sebanyak 256 siswa kelas VII salah satu SMP di Kota Salatiga Tahun Pelajaran 2018/2019 yang terbagi dalam 8 kelas. Melalui teknik cluster random sampling, terpilih siswa kelas VIIE sebagai kelas eksperimen dan siswa kelas VIIH sebagai kelas kontrol.  Teknik Pengambilan data kemampuan pemecahan masalah matematik melalui pretest dan posttest. Teknik analisis data menggunakan independent sample t-test pada N-Gain score. Hasil penelitian menunjukkan bahwa penerapan model problem posing tipe pre-solution posing lebih efektif terhadap kemampuan pemecahan masalah matematik siswa dibandingkan siswa yang mendapatkan pembelajaran secara konvensional.