///Using 1861 P wave arrival times from 460 local earthquakes (ML≥1.0) recorded by the Handan Seismic Network from 2001 to 2008, the authors use the simultaneous inversion method to determine the hypocentral distribution and velocity structure in the juncture area of Shanxi, Hebei, Shandong and Henan provinces. The results show that: 1) after the simultaneous inversion of earthquake relocation and velocity structure, residual root mean square (RMS) of P wave travel time decreased from the 1.35 s to the 0.45 s; 2) small and medium earthquakes spread in the NEE direction in the Xingtai hypocentral area, with focal depths varying from 7 to 14 km; seismicity displays two conjugated distributions in the directions of NEE and NNW in the Cixian hypocentral area; and 3) low velocity layer exists in 7~14 km beneath the meizoseismal area of Xingtai earthquake, consistent with the focal depth of Xingtai M7.2 earthquake.