Abstract: ZnAl₂O₄ and La³⁺ (from La₂O₃) doped Ca_0.61Nd_0.26TiO₃-MgTiO₃ powders were synthesized by solid-state reaction method, which were used for preparing ZnAl₂O₄ and La³⁺ doped Ca_0.61Nd_0.26TiO₃-MgTiO₃ composite ceramics through dry-pressing and sintering in air atmosphere. The effects of doping contents of La³⁺ and ZnAl₂O₄ on the microstructure, phase formation and dielectric properties performance of the composite ceramics were investigated. The results show that ZnAl₂O₄ additive can adjust the crystallite size, so the density of the sintered ceramics increases with the increase of La³⁺ and ZnAl₂O₄ contents. The dielectric constant and temperature coefficient of the composite ceramics decrease with the increase of ZnAl₂O₄ content, but are not significantly affected by the La³⁺ content. The quality factor of the composite ceramics increases first and then decrease with the increase of ZnAl₂O₄ content. The obtained composite ceramics with a sintered density above 94% displays good dielectric properties, such as dielectric constant is about 40-50, temperature coefficient is less than 40×10^-6℃^-1 and quality factor is larger than 38 000 GHz. Thus ZnAl₂O₄ and La³⁺ doped Ca_0.61Nd_0.26TiO₃-MgTiO₃ composite ceramics can be used in the field of communication technology.