Data from K-NET and KiK-net were used to evaluate regional site effects in the Kanto region. The present study delineates some of the shallow soil/bedrock engineering characteristics for construction purposes. A number of engineering parameters, such as Concentration Index Ci, Material Index γ, Density Gradient Di and Stress Ratio Si, were estimated using K- and KiK-NETS data together with shallow/deep borehole recordings obtained from the pre-Tertiary basement. Estimated parameters, which include seismic velocity values, engineering, consolidation and strength parameters showed that, these parameters are strongly correlated with the structure of the sedimentary layer-bedrock system in the Kanto region. The present study also delineates the usefulness of the K-NET and KiK-net data, which are now available on the internet site (www.k-net.bosai.go.jp/).