The Sichuan University Museum has a massive collection of ancient books and archives. The collection has long history and great value. Now, after longterm storage the books are suffering from different degrees of deterioration and need to be repaired and preserved utilizing scientific concepts. In this study, survey of the state of deterioration of these books has been carried out and the books has been analyzed by nondestructive or microdestructive methods, such as acidity measurement using a pH meter, optical microscopy, Fourier transform infrared spectrometry and scanning electron microscopy with energy dispersive Xray spectrometry. The results showed that these books suffered from different degrees of worm, mildew, moisture, pollution, fracture and embrittlement damage. The analysis revealed that these ancient papers are mainly pulped with bamboo and straw fibers. CaCO₃ can reduce acidification of the paper. The lack of alkaline substance such as CaCO₃ in the pulp, the growth of mildew on the surface and the addition of alum or iron during the production process all probably accelerate the acidification of papers.