Abstract:The improved LDA topic model and FCM user clustering algorithm are integrated into UserCF to solve the problem of semantic missing and low precision of current knowledge recommendation algorithm. An adaptive function is constructed to achieve an objective solution of the number of topics and the knowledge topic of interest to the user is mined through LDA. FCM algorithm is used to cluster the user topics, and the users are divided into clusters with similar interests, thereby narrowing the traversal range of the user similarity calculation. The JS divergence is used instead of the Euclidean distance to convert FCM object to user. Finally, based on the UserCF algorithm, the user's interest index on knowledge is constructed, and the user is recommended by TOP-N. The comparison results show that the precision, recall and F1 value of the proposed algorithm are increased by 28.17%, 59.62%, 53.88%.