A dielectric ceramic composition for high frequencies consisting essentially of 83 to 99.8 wt% of a basic composition composed of 22 to 43 wt% of titanium dioxide, 38 to 58 wt% of zirconium dioxide and 9 to 26 wt% of stannic oxide, and 0.2 to 17 wt% of one or two addditives selected from the group consisting of lanthanum oxide, cobaltic oxide and zinc oxide. The dielectric ceramic composition has high permittivity and high Q and is suitable for use as dielectric resonators in microwave bandpass filters, or as antennas employed at microwave frequencies, or as substrates for microwave circuits.