The effects of inert fillers, such as quartz and Al2O3, on the sintering behavior and physical properties of lead borosilicate glasses used for barrier ribs of plasma display panels (PDP) were investigated. The effects of volume fraction and type of filler on the sintering temperature, thermal expansion coefficient, dielectric constant, and fracture resistance of the barrier ribs of PDP were investigated. The influence of the filler on sintering behavior was discussed based on the wetting angle of the glass on the fillers. The physical properties and fracture resistance of the glass with fillers were measured and compared with theoretical models.