Currently, social information services (SIS) have become one of the important sources of information and allow any user to distribute information without restrictions, which makes it difficult to determine the degree of reliability of information. Revealing unreliable facts from the news using artificial intelligence methods is a difficult problem. To solve this problem, it is necessary to apply several existing models with the calculation of the reality parameter and recognition accuracy, as well as to develop a new algorithm for detecting fake news. The use of effective tools for identifying false information in the SIS and the corresponding algorithm is considered in support and decision-making systems, when determining the degree of information reliability