The water conductivity of karst collapsed column is affected by multiple factors such as the characteristics of its own column filling, structure and mining disturbance. As a structural water-conducting channel, fault usually plays a controlling role in hydrogeological structure. During the process of mine water hazard prevention and control, it was discovered that the lithology composition, compaction and cementation degree and water physical properties of karst collapsed column fillings were all non-conducting water, but due to the influence of combined development faults, some exploration drill holes showed concentrated water outflow. Based on this, the scientific hypothesis was proposed that fault cutting leads to water conduction in karst collapsed columns. The study comprehensively used methods like chronology, exploration data analysis, and hydrochemical testing to analyze the chronological relationship between faults and karst collapsed columns, their spatial relationship, outlet point distribution and water chemical properties, and the impact of faults on the water-conductivity of karst collapsed columns, which proved the effect of fault cutting on changing water conductivity of karst collapsed column. The research showed that later fault cutting through karst collapsed columns turned the originally non-conductive karst collapsed columns into water-conductive collapsed columns at the fault plane, creating a longitudinally connected water-conducting channel. A new model of fault cutting karst collapsed column to change the original water conductivity of karst collapsed column was proposed. The research results can provide a theoretical basis for the prediction of the water conductivity of the karst collapsed column. According to whether the karst collapsed column was cut by the fault, it was predicted theoretically, so as to determine the key areas of water conductivity detection and prevention and control, and has broad application prospects under the background of source control of mine water disaster.