The bagasse fly ash (BFA), an industrial solid waste of sugar industry, was used to facilitate the clarification of cane juice. After being grounded, washed, rinsed and dried, the BFA was added into the juice before the clarification process including heating the juice to 60°C, coagulation with magnesium sulfate at pH=11.0, flocculation with PAM, and then settling and filtration. The effect of BFA on purification indexes including turbidity, purity and color value of the clarified juice, and the addition of BFA on the settling and filtration rates were investigated. The results shown that while having little effect on the pufification indexes, the addition of BFA could intensify the solid-liquid separation of the clarification. The gravity settling was significantly improved with the addition of BFA, with an addition at 1.5%, the mud thickening rate at free settling phase was increased from 20.7 mL/min without addition of BFA to 270mL/min and the final mud volume reduced from 48.0% of the total volume to 32.3%, the settling time being about 5 minutes. With the addition of BFA, the filtration rate increased significantly, the filter cake specific resistance was reduced from 562.8 kg·s·m-4 without addition of BFA to 31.2kg·s·m-4 with the BFA addition of 1.5%, making the filtration feasible. The optimum addition of BFA and the pressure drop for the filtration were 1.5% and 0.1MPa respectively.