In this paper, usage of decision support systems in information operations recognition is described. Based on information of experts, the knowledge engineer constructs a knowledge base of subject domain, using decision support system tools. The knowledge base provides the basis for specification of queries for analysis of dynamics of respective informational scenarios using text analytics means. Based on the analysis and the knowledge base structure, decision support system tools calculate the achievement degree of the main goal of the information operation as a complex system, consisting of specific informational activities. Using the results of these calculations, decision makers can develop strategic and tactical steps to counter-act the information operation, evaluate the operation?s efficiency, as well as efficiencies of its separate components. Also, decision support system tools are used for decomposition of information operation topics and evaluation of efficiency rating of these topics in dynamics. Keywords: Information operation; Decision support system; Expert estimate; Content-monitoring system