The article proposes the approach to intellectual decision support in the field of software requirements engineering based on OWL-ontology. The approach presented takes into account the specifics of requirements engineering for agile project management. The architecture of the developed decision support system consists of a user interface, a Python application including the reasoner, the OWL ontology and the file database. OWL ontology accumulates knowledge about the criteria for assessing the quality of requirements. The ontology enables accumulating in the form of instances of class’s information about the software product requirements, requirements artefacts, and requirements sources. The ontology includes the axioms of descriptor logic, enabling to perform reasoning about the requirements, to identify the implicit relations between the requirements. The ontology includes the knowledge that is necessary to analyze the correspondence of user stories and behavior scenarios to the criteria for evaluating their syntactic quality, to determine the priority and risk level of user stories. Also, the ontology enables bottom-up or top-down tracing of requirements and assessing the completeness of individual requirements. Application of the developed system ensures to lessen the wrong decisions number with management of requirements to the software.