Abstract:Constructing a book recommendation system can not only allow users to quickly and effectively obtain the re ̄ quired book information and reduce information overloadꎬ but also can make better use of the potential value of the library' s collection of book resources.On the basis of summarizing several common recommendation algorithmsꎬ the implementation process of recommendation algorithm based on collaborative filtering is givenꎬ and the optimization scheme and the opti ̄ mized algorithm implementation process are given for its cold start and data sparsity. The results show that the user charac ̄ teristic attribute and user clustering method were introduced into the algorithmꎬ which effectively reduced the data sparsity problemꎬ improved the recommendation efficiency of the algorithmꎬ and solved the recommendation algorithm design in the book recommendation system to a certain extent. The optimized algorithm can be used in the design of library book recom ̄ mendation system.