In the last few years the embedded systems design discipline required new design methodologies and new specification languages to support system engineers in developing heterogeneous systems where hardware and software are combined. One of the emerging modeling languages for system designers is the UML-based language called Systems Modeling Language (SysML). One of the most important tasks to be addressed early in the system design phase is the Design Space Exploration (DSE). DSE helps designers in discovering the optimal solutions among all possible combinations after mapping functional to architectural specifications. This paper describes an approach on how to use SysML for a DSE analysis within a system design phase.