In the teaching of discrete mathematics, there are many interrelated knowledge points, and students often face challenges of poor memory and confusion. In addition, there are significant differences in learning ability among students, and traditional teaching methods are insufficient to meet individual needs. Therefore, intelligent and digital teaching methods are needed to assist learning. This chapter introduces the design and implementation of an intelligent auxiliary learning system for Discrete Mathematics based on the knowledge graph technology. The system includes a “test and diagnosis” module, an intelligent question and answer module, a learning resource library, and an exercise library. The knowledge system of discrete mathematics is constructed through knowledge graph, and the learning resources and exercises are associated with knowledge points and methods. Students can test by selecting exercises from the exercise library based on the defined knowledge scope or randomly selected questions through the system. For the knowledge points that are not well mastered, they can ask questions through the intelligent question and answer module to understand relevant concepts or obtain relevant learning resources. Using the system can help students better organize and understand the content of discrete mathematics knowledge points, build discrete mathematics knowledge system, diagnose weak knowledge points and skills in the learning process, and meet the targeted personalized learning needs. The system architecture can also be applied to assist in learning other courses.