In this paper, we present piezoelectric energy harvesters with pillar- and bulk-type multilayer ceramic–polymer composite structures as energy sources. The 0.2(PbMg1/3Nb2/3O3)–0.8(PbZr0.475Ti0.525O3) ceramics were sintered and poled using the conventional ceramic process. The piezoelectric ceramics were prepared in the form of rectangular pillar- and cylindrical bulk-type structures and were attached to the metallic bottom electrode with poled states. Symmetric upper electrodes were attached to the other side. The pillar- and bulk-type ceramic structures were filled with polydimethylsiloxane (PDMS). Subsequently, the two ceramic structure types were manufactured with single-, double-, and triple-layer devices. Both the multi- and single-layer devices were compared using several analysis methods. The piezoelectric properties, including the piezoelectric constant, are discussed in this paper. We also studied the output power of the multi- and single-layer devices.