(1−x)ZnO–xMgO–0.88TiO2–0.12SnO2 (x=0.05, 0.10, 0.15 and 0.20) ceramics were prepared by conventional mixed-oxide method. The phase structure, morphology and dielectric properties of the ceramics were investigated. The results show that Mg was incorporated into the phase of Zn2(Ti,Sn)O4 and the spinel-type solid solution (Zn(1−x),Mgx)2(Ti0.88,Sn0.12)O4 formed, the solid solubility limit of Mg was situated at x=0.05–0.10. The 0.95ZnO–0.05MgO–0.88TiO2–0.12SnO2 ceramics sintered at 1080°C exhibit dielectric properties εr=18.9, tanδ=5.5×10−4 and near zero temperature coefficient of dielectric constant (τε=2.89ppm/°C). Due to their stable dielectric property, the 0.95ZnO–0.05MgO–0.88TiO2–0.12SnO2 ceramics can serve as the promising high-frequency dielectric capacitor after further modification.