The paper describes an approach to developing a computer system automated build basic ontology.This approachbases to natural language text documents analysis. There is described the method for semantic analysis of documents using the software Link Grammar Parser and machine learning techniques. Machine learning tools operate in conjunction with OWL- ontology. Ontology gives grammatically templates and semantic structures for recognition statements (predicate logic of 1st order) in patients and / or educational texts. As a result of the recognition are new items that are added to the ontology. There is built the architecture synthesis system ontology. The basic modules of the system and their purpose are described. Authors choose the software tools for the practical implementation of the system. There is done the practical implementation of the proposed method. The functionality of the developed system has tested. The system allows in automatic mode to fill the domain ontology.