Abstract: 0-3 cement-based piezoelectric composites were fabricated by compressing technique, with sulphoaluminate cement as the matrix, Pb(Zr_0.52Ti_0.48)O₃(PZT)/ceramic as the functional phase. The effects of forming pressure on the cement-based composites of different size PZT particles were investigated. The results indicate that the change in forming pressure affect the piezoelectric and dielectric properties of PZT/cement composites of different size PZT in different ways. In the forming pressure range from 30 MPa to 90 MPa, the piezoelectric strain factors (d₃₃) and the relative dielectric constants (ε_r) of PZT/cement composites rapidly increase as forming pressure adds due to the reduction of porosity with pressure. However, the change in piezoelectric voltage factors (g₃₃) with pressure is related to the size of PZT. The electromechanical coupling coefficients (K_t and K_p) of PZT/cement composites of different sized PZT particles also have distinct changes with forming pressure. For PZT/cement composites of 6 μm or 126 μm size PZT particles, the K_t and K_p reduce with the increasing of forming pressure, while that of composites of 430 μm size PZT particles goes up as forming pressure rises. In addition, both dielectric and piezoelectric performance degrade significantly when forming pressure is up to 150 MPa.