Bauxite-based mullite grogs were prepared with grade II bauxite (≤3 mm)and coal gangue (≤3 mm) as starting materials with formula of w（Al2O3）＝68%–72％. Mill the mixture to particle size ≤0.044 mm by wet milling to homogenize chemical composition. After shaping by wet extrusion and drying, the materials were fired at 1 550 ℃, 1 600 ℃ and 1 700 ℃ for 6 hours respectively. After cooling apparent porosity and bulk density of fired materials were tested. The results show as follows: the appropriate sintering temperature for bauxite-based mullite with homogeneous and consistent composition and microstructure and properties is 1 600 ℃, at which the mullite has apparent porosity ≤1.5%, bulk density ≥2.81 g?cm–3 and refractoriness under load is 1 610–1 650 ℃. Compared with the laboratory results, the sintering temperature is lowered about 100 ℃, bulk density increased 0.06 g?cm–3. The industrial feasibility of preparing bauxite-based mullite grogs with the processing is confirmed.