For low temperature co-fired ceramics (LTCC) materials, glass-ceramic composites consisting of a BaNd2Ti5O14 ceramic and the lead-free rare earth derived boron glasses (L glass) were tested with different frit size. The glass-ceramic composites were evaluated for thermal properties and microwave dielectric properties (epsilon(r), Qf(0): quality factor). At low temperature, the sintered body demonstrated applicable properties such as high relative density of over 80% and various dielectric properties, namely, 17-20 for epsilon(r) and 3376-10,000 GHz for Qf(0). The results suggest that the microwave properties are controlled by frit size for low temperature co-fired ceramic compositions at high-frequency application. (C) 2006 Elsevier B.V. All rights reserved.