Abstract: Based on focal depth data of Fujian digital seismic network, we analyzed 1431 M_L≥1.0 earthquakes with focal depth and first class observation accuracy occurred in Fujian province and vicinities from July 1998 to June 2008. With the meshes of 0.4°×0.4°and the sliding step of 0.2°, the average focal depth in every mesh was calculated, and contour map of average focal depth was plotted. The results can be summarized as follows: ① The characteristics of focal depths in the region is deeper in the southeast than in the northwest. The average focal depth is more than 14 km in the southeast costal region and less than 10 km in the northwestern region(Nanpin City area); ② The isolines are mainly in NE direction. The focal depth is controlled by NW-trending structure and relatively deep in fault structure areas in the southern; ③ The earthquake dynamic cause in Fujian region may be different from the other parts of the China continent.

Key words: Focal depth Distribution, Statistical Analysis, Seismic structure, Fujian Region