The 2 051 earthquakes are relocated and their focal depths are determined by using Powell scanning method and time difference of P and S wave from earthquake data observed from 1984 to 1993 at 79 local seismic stations in the zone of 103°~113°E, 31°~39°N in Shaanxi,Shanxi, Henan, Hubei, Gansu and Ningxia provinces.The maps of distribution of present earthquake epicenters,spatial distribution of present earthquake sources,isogram distribution of average focal depths and longitudinal and latitudinal sections of focal depths of present earthquakes in and around the Weihe downfaulted basin are drawn. On the basis of above-mentioned works the regularity of spatial distribution of earthquake sources are studied. The results show that the non-uniform spatial distribution of earthquake sources in and around the Weihe downfaulted basin basically reflects the differences of seismicity level of the region and closely related to the difference of geotectonics and heterogeneity of crustal velocity structure of the region.