In this study, we investigate the effective characteristics of a porous piezocomposite with randomly distributed pores of arbitrary size and with partly metalized pore boundaries. Using the ANSYS APDL finite element software, we created a novel random representative volume element (RVE), applied the finite element approach to solve boundary value problems of homogenization, and calculated equivalent properties using the Hill–Mandel principle. The results demonstrate that when large random RVE and an appropriate finite element mesh are used, the porous piezocomposite with randomly metalized porosity borders will have the same crystal symmetry as the piezoceramic matrix. Therefore, when there is a significant material contrast between the various phases, a large random RVE is preferred in the modeling of particulate-filled composites. Furthermore, when the areas of metalized surfaces increase, the performance of the investigated composite in transverse sensing and actuation applications improves.