Biological piezoelectric materials have significant potential for bone repair and energy harvesting owing to their excellent biocompatibility and piezoelectric effect. The BaTiO₃/Ca₁₀(PO₄)₆(OH)₂ (BT/HA) composite material is an outstanding representative of biological piezoelectric materials, which has not been individually designed using digital light processing (DLP) 3D printing because of the large difference in the refractive index of its components. Therefore, in this work, double-sided-tooth plate-like BT crystals with high curvature were prepared via a hydrothermal process, and BT/HA ceramic slurries were grinded out using dispersed intermittent ball milling scheme, and BT/HA nanocomposite ceramic scaffolds were fabricated by DLP 3D printing technology. The nanostructure, dielectric properties, and piezoelectric energy harvesting performance of the BT/HA nanocomposite ceramic scaffolds were evaluated. The influences of different morphologies and contents for BT on the piezoelectric potential and stress distribution were analyzed based on a multi-physics coupling finite element simulation. The cell proliferation and adhesion abilities were investigated also. The BT/HA nanocomposite ceramic scaffolds present excellent dielectric properties, cell proliferation and adhesion abilities, and an open circuit voltage of 8 V during piezoelectric energy harvesting. The material properties and multi-physics coupling finite element analysis imply that the double-sided-tooth plate-like BT plays an important role for the fastness structure and electric field distribution in the BT/HA nanocomposite. Thus, this work provides a strategy for the application of the customized BT/HA nanocomposite ceramic scaffolds in new-generation orthopedic implants and biological energy harvesting.