The creation of interactive 3D presentations is typically a complex process involving activities related to various aspects of the contentsuchasgeometry,structure,space,appearance,logicandbehaviour.However,widespreaddisseminationofinteractive3D content on the web requires flexible and efficient methods of content creation. In this paper, an approach to semantic modelling of 3Dcontentisproposed.Theproposedsolutionenablescreationofcontentcomponentsandproperties-reflectingdifferent aspects of the content - with domain-specific ontologies and knowledge bases. The use of domain-specific knowledge liberates authors from going into details that are specific to 3D modelling, allows for content representation at different levels of abstraction and permits content creation by domain experts, who are not required to be IT-professionals.