As one of the cutting-edge technologies for knowledge organization and management, knowledge graph is gradually becoming an important force driving the in-depth development of digital humanities research. Its unique semantic correlation ability is conducive to revealing the complex connections and deep knowledge structures hidden in textual information, opening up new perspectives and paths for cultural inheritance and innovation. As one of the three mysterious books of ancient times, the Classic of Mountains and Rivers contains profound cultural and research values. Taking the Classic of the Southern Mountains in the Classic of Mountains and Rivers as a specific example, this paper systematically constructs a set of metadata description system for the Classic of Mountains and Rivers, and introduces Protege and Neo4j to build domain ontology and knowledge graph, revealing its internal knowledge structure and logical relationship. This provides a useful exploration and practice for the application of knowledge graph in the field of digital humanities.