With the acceleration of modernisation and changes in the surrounding environment and human factors, the survival of some traditional ethnic sport’s intangible heritage is threatened, and the related protection work needs to be improved urgently, and digital technology provides new technical means and ways for it. In this paper, we construct a knowledge map of traditional sport’s intangible cultural heritage of ethnic minorities based on a graph database, use Cypher query language to achieve the visual presentation of traditional sport’s intangible knowledge and conduct visual knowledge discovery of intangible knowledge from various aspects as well as the use of semantic similarity to calculate the relationship between the non-heritage knowledge and the mining of the law of evolution and then realise the digital protection of non-heritage. Knowledge graph design is carried out for 37 traditional minority sports in X city, and the results show that the visual display of traditional sports NRL knowledge based on a knowledge graph has the feasibility of promoting the protection and inheritance of traditional sports.