Effects of ceramic filler types and dose on the low temperature sintering and dielectric properties of ceramic/$CaO-Al_{2}O_{3}-SiO_2$ (CAS) glass composites were investigated. All of the specimens were sintered at $850{sim}900^{circ}C$ for 2 h, which conditions are required by the low-temperature co-firing ceramic (LTCC) technology. Ceramic fillers of $CaCO_3$, $Al_{2}O_{3}$, $CaCO_3-Al_{2}O_{3}$ mixture, and $CaCO_3-Al_{2}O_{3}$ compound ($CaAl_{2}O_{4}$), respectively, were used. The addition of $Al_{2}O_{3}$ yielded the crystalline phase of alumina, which was associated with the inhibition of sintering, while, $CaCO_3$ resulted in no apparent crystalline phase but the swelling was significant. The additions of $CaCO_3-Al_{2}O_{3}$ mixture and $CaAl_{2}O_{4}$, respectively, yielded the crystalline phases of alumina and anorthite, and the sintering properties of both composites increased with the increase of filler addition and the sintering temperature. In addition, the $CaAl_{2}O_{4}$/CAS glass composite, sintered at $900^{circ}C$, demonstrated good microwave dielectric properties. In overall, all the investigated fillers of 10 wt% addition, except $CaCO_3$, yielded reasonable sintering (relative density, over 93 %) and low dielectric constant (less than 5.5), demonstrating the feasibility of the investigated composites for the application of the LTCC substrate materials.