The dielectric properties (epsilon and tan delta) of MZT-based ceramics can be tailored at both 1 MHz and the terahertz (THz) frequencies (0.2-2 THz) by CaTiO3 (CT) doping. CT was formed liquid phase during the sintering process and accelerated the densification of the ceramics. Doped with CT, the increase of the epsilon at 1 MHz could be explained by Lichtenecker expressions equation, and the tan delta is decreased at 1 MHz due to the high density. By doping with CT, the THz dielectric properties of ceramics can be modified, due to the variation of the lattice parameter and microstructure (porosity). At THz frequencies, ion displacement polarization is difficult to achieve, so that epsilon at THz is smaller than epsilon at 1 MHz according to Clausius-Mosotti equation. According to the four-parameter factorized oscillator model, the tan delta is increased with frequency up to THz frequencies. The power absorption of the MZT-based ceramics is lower than 10 cm(-1) below 1 THz, and it is a good choice as a transparent material at terahertz domain, which may promote the development of terahertz devices.