This study aims at exploring composite materials based on polymer matrix for microelectronics application. Materials used for such applications need to have added multifunctional properties. Up to now, a sole polymer or single filler-filled polymer composites is tough to satisfy the demand for more multifunctional properties, particularly to acquire high effective thermal conductivity and low-dielectric constant simultaneously. In this study, hybrid filler systems i.e. aluminum nitride of average particle size 60 to 70 micron and solid glass microspheres of 90 to 100 micron were incorporated into epoxy matrix in an attempt to reach a composite with such desired properties. By varying the volume fraction of fillers (5 to 25% for aluminum nitride and 5 to 10% for solid glass microspheres), a new kind of epoxy-matrix composite is fabricated on a laboratory scale by simple hand lay-up technique keeping in mind the fact that the future electronic packaging materials would possess high heat dissipation capability, high glass transition temperature, low coefficient of thermal expansion and low dielectric constant for appropriate functioning of the electronic substrate. In addition, the measured thermal conductivity is compared with calculated values obtained from the proposed mathematical model and found that they are in better agreement with the values obtained from the pro- posed correlation.