Abstract: The theoretical bases and tools of the organization of cloud platform monitoring systems in modern conditions are investigated in the article, using the system approach as a methodological basis for the study of cloud technology monitoring. A generalized model of user behavior and interaction of entities in the cloud system is proposed as a fuzzy undetermined digital automaton The architecture of cloud platforms is analyzed. A block diagram of the cloud platform and subsystem monitoring of user behavior and entity interaction has been developed, which monitors all inputs, outputs of users, entities and systems as a whole, keeps track of its operations, and implements permitted transitions in accordance with monitoring rules. This model of analysis of actions of users and actors of cloud platforms is an element of the monitoring system of the cloud platform and will help to increase the level of security of cloud computing systems. A model for monitoring user behavior and the interaction of entities in the cloud system is a signature model for looking for prohibited activities in the cloud platform system. The proposed algorithm for analyzing user behavior in the cloud platform system is designed to develop a monitoring system. The proposed approach will improve the security of the platform by increasing the reliability of detection of unauthorized requests and actions of users, as well as participants of interaction in the cloud system. Expert-analytical methods will allow to determine the general level of criticality of the system of protection of the cloud platform, its weaknesses, in order to obtain the total sum of estimates for all information resources. These methods help identify items that need maximum protection. Further studies should focus on complementing this model with the calculaion of risk factors in monitoring cloud-deployed cloud services