Ferroelectric topological vortex domains have attracted interest for their unique properties and potential in next-generation electronics. However, their role in bulk ferroelectrics remains poorly understood. Here, we identify topological vortex structures in bulk PMN-PT crystals and demonstrate their direct role in enhancing piezoelectric response, establishing a mechanistic link between vortex structures and macroscopic performance. We develop a straightforward and scalable method, mechanically assisted electrical poling, to engineer vortex domain density, which increases the vortex core density from 0.01 μm⁻² in conventionally poled samples to 21 μm⁻². This controlled domain engineering leads to a remarkable improvement in piezoelectric response, primarily attributed to the localized strain fields surrounding the vortex cores. This study represents a major step forward in understanding the topological structures in bulk ferroelectrics, opens up a practical pathway to engineer high-performance ferroelectric materials for future innovations in device applications.