β-eucryptite ceramics with zero coefficient of thermal expansion (CTE) were prepared via solid state reaction method, adding CaO-B 2 O 3 glass (CB glass) as sintering aid. The thermal property of CB glass and the crystalline phase, micro-structure of β-eucryptite ceramic samples were investigated by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. The results indicate that CB glass is a good sintering aid. It significantly decreased the sintering temperature of β-eucryptite ceramics (from 1300 to ℃ 1150℃) and increased the relative bulk density (from 93.3% to 97.5%). No micro-cracks were found in β-eucryptite ceramics aided with CB glass. β-eucryptite ceramics added with 4wt%, 6wt% CB glass possessed zero CTE of 0.02×10-6 /K and 0.4×10-6 /K ranging from room temperature to 200℃, respectively. However, a new phase LiAlO 2 with extremely high positive CTE appears in the β-eucryptite ceramics added with 8wt% CB glass which leads to a positive CTE of 3.46×10-6 /K.