In this work, dependence of electric energy output of impacted piezoelectric element on impact conditions is experimentally investigated. Investigated impact parameters include impact position, radius of impact sphere, orientation of the hitting object, and material and configuration of the buffer layer. It is found that the electric energy output of impacted piezoelectric plate may be increased by impacting the buffer layer at its center, decreasing the contact area between the hitting object and buffer layer, reducing internal energy absorption in the mechanical buffer layer and avoiding wave reflection in the buffer layer. The experimental phenomena are theoretically explained and analyzed, based on the piezoelectric constitutive equation and Hertz's impact theory. (C) 2011 Elsevier B.V. All rights reserved.