A new low loss microwave dielectric ceramic with composition of CoLi2/3Ti4/3O4 was prepared by a conventional solid-state reaction method. The compound has a cubic. spinel structure [Fd-3m (227)] similar to MgFe2O4 with lattice parameters of a = 8.3939 angstrom, V = 591.42 angstrom(3), Z = 8 and rho = 4.30 g/cm(3). This ceramic has a low sintering temperature (similar to 1050 degrees C) and good microwave dielectric properties with relative permittivity of 21.4, Q x f value of 35,000 GHz and tau(f) value of -22 ppm/degrees C. Furthermore, the addition of BaCu(B2O5) (BCB) can effectively lower the sintering temperature from 1050 degrees C to 900 degrees C and does not induce much degradation of the microwave dielectric properties. Compatibility with Ag electrode indicates that the BCB added CoLi2/3Ti4/3O4 ceramics are good candidates for LTCC applications. (C) 2012 Elsevier Ltd. All rights reserved.