Abstract: In order to find out the water bursting channels in limestone aquifer under coal seam floor in working face 63301 of Xinzhuangzi coal mine, NaCl was adopted as the tracer and put into Taiyuan and Ordovician limestone aquifers. In the same case, KI tracer was put into observation wells in Cambrian limestone aquifer. Water samples were collected at intervals of the water inrush point at working face.63301. According to the curve of relationship between the concentration and time, the results of test and analysis indicate that there are many small channels and a large channel in the floor limestone aquifers of Taiyuan formation. Many channels are in Ordovician limestone aquifer, while Cambrian limestone aquifer has only 2 channels. The water flowing velocity in different limestone aquifer channel varies, showing the developmental heterogeneity of its karst fissures. Besides, limestone aquifer parameters are calculated with water inrush data. The above work provides an important reference for further study on the prevention and control of water hazards from Taiyuan limestone floor.