Abstract: Object oriented languages have wide applications in software engineering practice, and designing a rigorous semantics framework for these language has great importance in understanding their key features, and also in software verifications etc. This paper presented a new imperative-style semantics framework for object-oriented languages. This framework includes the operational semantics and a type system. I}his paper proved the soundness theorem.

Key words: Object oriented languages,Type systems,Operational semantics,Semantics framework