(1 - x)Nd(Co1/2Ti1/2)O-3(NCT)-xCa(0.8)Sr(0.2)TiO(3) (CST) composite ceramics were prepared by the conventional solid-state reaction process. From the X-ray diffraction analysis, it indicates that the Nd(Co1/2Ti1/2)O-3 phase coexists with Ca0.8Sr0.2TiO3 phase, and it is easy for the cobalt volatilization to form second-phase Nd2Ti2O7 as x = 0.5 and 0.7. As the content of CST increases from 0.1 to 0.9, the dielectric constant of the (1 -x)Nd(Co1/2Ti1/2) O-3-xCa(0.8)Sr(0.2)TiO(3) composite ceramics increases from 29.3 to 114.7, the Q x f value decreases from 60,000 to 8,500 GHz, and the tau(f) value varies from -33.8 to 271 ppm/degrees C. A near zero tau(f) could be achieved at 0.5NCT-0.5CST ceramics with epsilon(r) = 44.5 and Q x f = 20,000 (GHz) sintered at 1,340 degrees C for 4 h.