Against the dual backdrop of the digital transformation of education and the quality and efficiency improvement of teacher education, the curriculum system for physics major in normal universities is confronted with practical predicaments such as fragmented knowledge, weakened interdisciplinary connections, and disjointed competency cultivation. Based on constructivism theory, connectivism learning theory, and teacher professional development theory, this paper introduces knowledge graph technology and constructs a “three-dimensional integrated” optimization framework for the curriculum system. By sorting out the core competencies and graduation requirements of physics major in normal universities, extracting knowledge nodes, ability nodes, and competency nodes in the curriculum system, and using Neo4j and CiteSpace tools to draw disciplinary knowledge graphs, teaching ability graphs, and interdisciplinary integration graphs, a visualized curriculum correlation network is formed. Taking the 2022 and 2023 grade students of physics major at Chengdu Normal University as the empirical subjects, a comparative study shows that the optimization of the curriculum system from the perspective of knowledge graph can effectively solve the structural defects of traditional curricula, realize the coordinated development of “knowledge-ability-competency,” and provide a replicable and promotable practical paradigm for the reform of the curriculum system of science majors in normal universities.