Abstract: The experiments were carried out through mixing the high fluorine-containing acidic cryolite mother solution with the high fluorine-containing alkaline cryolite mother solution from the fluoride plants according to the proportion of 1 to 1.5.The experimental results showed that the difficulty of wastewater treatment was reduced obviously.The mass concentration of residual fluoride in the treated clean water was 8.75 mg/L,which lower the National Discharge Standard.The proper treatment conditions obtained from the experiments were：the dosage of Ca(OH)<SUB>2 </SUB>and soluble calcium salts was 2~2.5 times of theoretical amount;the quantity of high-effective fluorine removing agent and high-molecular flocculant (PAM) were 250 mg/L and 10 mg/L respectively;the pH was controlled at the range of 8.0 to 10.0;the stirring time was 45 min and the subsiding time was 60 min.<BR>