To reveal the key causes and their relationships in sports event safety incidents, this study employs social network analysis through Nvivo software to systematically examine 141 legal judgments on sports event safety accidents. The research identifies eight major categories of accident causes and 68 specific safety incident factors. Further, these 68 causative factors were used to construct a network for analyzing the causes of safety accidents in sports events. The results indicate that: (1) The network of causes for safety accidents in sports events exhibits small-world characteristics, with strong clustering of causes within the network, leading to rapid propagation. (2) The main causes of accidents in sports events stem primarily from the event organizers, followed by factors at the athlete and spectator levels. (3) Key causes of accidents include failure to arrange timely rescue operations, lack of safety supervision and guidance at the venue, athletes’ neglect of personal safety, failure to explain competition rules and precautions in detail before the event, lack of safety warning signs and protective equipment, and inadequate risk assessment of the event. (4) Insufficient rescue materials and medical aid devices, lack of risk prevention and emergency response plans, and failure to arrange timely rescue are common causes across all factions, increasing the incidence rate of safety accidents in sports events, and should be given special attention.