A new mixed system of Ca(CH₃CH₂COO)₂—H₂O—CH₃CH₂OH is used in deacidification of papercultural relics.Effect of different quantities of calcium propionate in the mixed waterethanol saturated solution,the ratio of water and ethanol,the volume of mixed solution,and the time of paper dipping in solution are studied for acidremoving from papercultural relics.The results suggest that the effect of acid removing from paper is better when calcium propionate is 3g in the waterethanol saturate solution.After immersed in the mixed solution,the value of paper's pH is about 7,the natural drying speed of paper is fast,no color changing and no crimple observed in the paper.