Traceability of software artifacts has been recognized as an important factor for supporting various activities in the software development process. Although recent research approaches facilitate the creation and refinement of the domain Ontology to ensure the consistency of the software artifacts during the software development, there is not enough attention to the importance of linking both software verification and artifacts traceability. This paper aims at improving the efficiency of the whole Rational Unified Process (RUP) software development by proposing an Ontology-based model. The domain Ontology is created and refined automatically from different UML artifact versions. The software artifacts released from the RUP iterations are verified automatically, and hence the artifacts traceability and the automatic software verification processes are facilitated at less cost, time and effort. To illustrate how to utilize the model, a case study and a simple discussion are presented.