Abstract: Hydraulic fracturing is a technique that is widely employed to increase the efficiency of coalbed methane (CBM) extraction.The evaluation of the spatial distribution of fractures produced by hydraulic fracturing is crucial for improving resource utilization and reducing potential gas outburst risks.In the process of hydraulic fracturing, microseismic events occur in tandem with the formation of cracks; therefore, microseismic monitoring can be used to evaluate the effect of hydraulic fracturing.At present, the microseismic monitoring of CBM hydraulic fracturing relies on the spatial distribution of microseismic events, which cannot accurately and comprehensively evaluate the effect of reservoir stimulation.In this study, the combined use of microseismic locations and velocity tomography was used to comprehensively evaluate the effect of CBM hydraulic fracturing.Based on the surface microseismic monitoring data of two CBM hydraulic fracturing wells in Shanxi, China, we used the double-difference seismic tomography method to determine seismic locations and velocity anomalies near the target coal seam.The location results showed clusters of microseismic occurrences in the vicinity of the fracturing well.Compared with the traditional location method, double-difference seismic tomography can obtain a more accurate spatial distribution of microseismic events, and this was used to estimate the fracturing area of the reservoir.Double-difference seismic tomography results showed that microseismic events were located in regions with relatively low v_P, high v_S, and low v_P/v_s anomalies.Combined with previous petrophysical experiment results, we speculated that methane was in a saturated state in the fractured areas, indicating that the hydraulic fracturing effectively released CBM.Therefore, the stimulation of coal seams can be described more comprehensively through microseismic event locations and tomography results.