A new mixed system of Ca(CH3CH2COO)2-H2O-CH3CH2OH is used in deacidification of paper-cultural relics. Effect of different quantities of calcium propionate in the mixed water-ethanol saturated solution, the ratio of water and ethanol, the volume of mixed solution, and the time of paper dipping in solution are studied for acid-removing from paper-cultural relics. The results suggest that the effect of acid removing from paper is better when calcium propionate is 3g in the water-ethanol 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.