ABSTRAK Penelitian ini bertujuan untuk mengetahui pengaruh model pembelajaran berbasis masalah terhadap hasil belajar serta peningkatannya. Materi fisika kuantum yang diteliti meliputi lima sub pokok bahasan yaitu: Persamaan Schrodinger, Operator Fisis, Komutator, Persamaan Gerak Heisenberg, dan Osilator Harmonis. Jenis penelitian ini adalah eksperimen dengan desain penelitian pretest and posttest group design. Populasi dalam penelitian ini adalah seluruh mahasiswa pendidikan fisika tahun pelajaran 2018/2019. Pengambilan sampel menggunakan teknik total sampling dengan mahasiswa semester VI A sebagai kelas eksperimen dan mahasiswa semester VI B sebagai kelas kontrol. Hipotesis penelitian diuji menggunakan uji-t dengan pretest and posttest dan peningkatan hasil belajar diuji menggunakan persamaan N-gain. Berdasarkan hasil uji hipotesis untuk hasil belajar fisika kuantum diperoleh nilai thitung (1,91)> ttabel (1,68) pada taraf signifikansi 5%, sehingga dapat disimpulkan bahwa terdapat pengaruh penerapan model pembelajaran berbasis masalah terhadap hasil belajar fisika kuantum bagi mahasiswa calon guru. Selanjutnya peningkatan hasil belajar fisika kuantum terlihat dari skor N-gain tertinggi pada kelas eksperimen terdapat pada sub materi komutator dan osilator harmonis sebesar 72%, sedangkan skor N-gain tertinggi untuk kelas kontrol terdapat pada sub materi osilator harmonis sebesar 60%. Kata kunci: model pembelajaran berbasis masalah;hasil belajar; fisika kuantum ABSTRACT This study aims to determine the effect of problem-based learning models on learning outcomes and their improvement. The quantum physics material studied includes five sub-subjects, namely: Schrodinger's Equation, Physical Operators, Commutators, Heisenberg's Equation of Motion, and Harmonic Oscillator. This type of research is an experimental research design with pretest and posttest group design. The population in this study were all physics education students for the 2018/2019 academic year. The sample was taken using total sampling technique with the VIA semester students as the experimental class and the VIB semester students as the control class. The research hypothesis was tested using the t-test with pretest and posttest and the improvement of learning outcomes was tested using the N-gain equation. Based on the results of hypothesis testing for the learning outcomes of quantum physics, the tcount (1.91) > ttable (1.68 ) is obtained at the 5% significance level, so it can be concluded that there was an effect of applying problem-based learning models on learning outcomes of quantum physics for prospective teacher students. Furthermore, the increase in learning outcomes of quantum physics can be seen from the highest N-gain score in the experimental class in the commutator and harmonic oscillator sub-material by 72%, while the highest N-gain score for the control class is in the harmonic oscillator sub-material by 60%. Keywords: problem based learning model; learning outcomes; quantum physics.