An additive manufacturing-enabled bi-continuous piezocomposite architecture is presented to achieve mechanical flexibility and piezoelectricity simultaneously in piezoelectric materials. This architecture comprises an active ferroelectric ceramic phase and a passive flexible polymer phase, which are separated by a tailorable phase interface. Triply periodic minimal surfaces were used to define the phase interface, due to their excellent elastic properties and load transfer efficiency. A suspension-enclosing projection-stereolithography process was used to additively manufacture this material. Postprocesses including polymer infiltration, electroding, and poling are introduced. Piezoelectric properties of the piezocomposites are numerically and experimentally studied. The results highlight the role of tailorable triply periodic phase interfaces in promoting mechanical flexibility and piezoelectricity of bi-continuous piezocomposites.