The invention provides a collaborative filtering recommendation algorithm fusing social trust influence, which comprises the following steps: step 1, preprocessing score matrix data of a project by users, filling and deleting unnecessary data, and calculating similarity among the users according to scores of the users; step 2, calculating a neighbor user set of the users; and 3, calculating the correct recommendation number of the user j to the user i, the local trust degree between the users and the global trust degree of each user according to the scoring matrix data of the user to the project. According to the invention, sparse user scoring information is fully mined; an implicit trust network is constructed, a local trust degree and a global trust degree are calculated through the scoring data; according to the method, the local trust degree and the global trust degree are combined to obtain the implicit trust degree, trust propagation of the users is considered for trust data between the users, the display trust relationship of the users is effectively expanded, and the problems of score matrix data sparseness and user cold start are relieved.