///Derived from Guangdong “10th Five” regional digital seismometry network are used in genetic algorithms along with joint inversion within Guangdong Province to acquire the one-dimensional velocity structure (horizontal layer) with minimum residual. With this basis and narrowed range, considering the actual circumstances of the distribution of seismic stations and epicenters, the entire study region can be divided into seven areas. Finally, through “stitching” and “comparison” of velocity structures of all seven areas, the regional three-dimensional velocity structures and the deep structures may be explored and studied. The results show that most earthquakes in Guangdong and its neighboring provinces occurs in the upper crust, e.g. 14.2 km above, and there are a few in the middle crust (14.2~22.5 km) .