Abstract: In order to study the causal factors of the “three-disobeying” of coal mine employees, a discussion was held with 96 miners who have recently committed “three-disobeying” in four coal mines in Ordos. Based on the behavior safety “2-4” model and using NVivo qualitative analysis method to analyze the discussion data, five tree nodes including unsafe states, unsafe actions, personal habits, organizational management loopholes, and lack of safety culture and their divergent 24 sub-nodes are summarized, and the logical relationship diagram of the “three-disobeying” behavior node is obtained, thus the specific cause chain of the “three-disobeying” of coal mine employees is established. By analyzing the coding data of the tree node of the “three-disobeying” behavior, and counting the sub-nodes of each tree node with the number of coded reference points, the node with the highest frequency in each part of the cause chain was determined. Research shows that sub-nodes such as equipment failure or tool damage(30.20%) and limited working space(23.96%) are important factors affecting unsafe states; inadequate hazard investigation and management(61.46%), improper use of labor protection products(53.12%), and inadequate safety monitoring (48.96%) are important factors leading to unsafe actions.