DSSA (domain-specific software architecture) is essential for the development of applications in the same domain. Feature-based domain model makes the mapping from domain requirements to DSSA possible. In this paper, ontology is introduced as the representation basis for feature models, and feature ontology of a domain is also taken as the semantic description basis for business components in the domain. Then a feature model and component semantics based method for conceptual architecture design are proposed. Commonality, variability, binding time, structural relations, and dependencies are taken into account in the method. The component semantics act as the transition from feature to conceptual component design. The methods have been implemented in the ontology-based feature modeling tool and feature-based architecture development tool, and exhibit effective supports for domain development.