In this study, ceramic composites of the Zn2Te3O8-TiTe3O8 system were adopted to improve the dielectric properties of the ultra-low-fire single-phase Zn2Te3O8. The ceramic composites were densified at 600 degrees C. The X-ray diffraction results show no interaction between Zn2Te3O8 and TiTe3O8 during sintering. Granular grains in the range of 1-5 mu m were observed, and the microstructural evolution was nearly independent of the TiTe3O8 content. Owing to the inertness between Zn2Te3O8 and TiTe3O8 ceramics, the dielectric constant (epsilon(r)) and the temperature coefficient of resonant frequency (tau(f)) increased nearly linearly, while the quality factor (Q x f) decreased with the content of TiTe3O8 in the Zn2Te3O8 ceramic. The Zn2Te3O8-30 wt% TiTe3O8 ceramic composite sintered at 600 degrees C reported the best dielectric properties with an epsilon(r) of 19.8, a Q x f of 50 042 GHz (at a measurement frequency of 11.8 GHz), and a tau(f) of 3.0 ppm/degrees C, qualifying the ultra-low-fire composites for use in ceramic resonators.