In this study, we investigated the role of mathematics in the construction of quantum physics knowledge through problem-solving with peers. In an undergraduate-level quantum theory course, 36 quantum physics problems covering different topics were given to students in four test sessions throughout the semester. Each test consisted of nine quantum physics problems categorized as structural or technical. After students solved all problems in a test individually, they solved them again with their peers in the group round. The analyses of the data showed that students’ arriving at the correct or incorrect answer with their peers for structural problems is context-independent; however, it is context-dependent for technical problems in quantum physics. In addition, when quantum physics knowledge is constructed, it is mostly based on structural problems in earlier topics and on technical ones in the latest topics of the quantum physics course.