Abstract: The densification process,phase shift,microstructure and dielectric properties of CABS/ Al₂O₃ system glass -ceramics were studied using DSC,XRD,SEM and EDS.The results show that densification has been achieved at 825℃and dielectric constant（ε_r） gets its maximum.At 850℃Anorthite precipitates from the matrix phase,which leads to the significant decrease of dielectric loss（tanδ）.With heat -treatment temperatures increasing,tanδ increases slightly due to the loose microstructure.The obtained glass-ceramics at 850℃which have ε_r of 7.9 and tanδless than 1×10^-3can be used as promising LTCC materials.