The mechatronics is affecting the modern Mechanical Engineering. The usage of electronics and software causes the complexity of the system development. To keep the complexity in check, the interdisciplinary approach "Model based Systems Engineering (MBSE)" is suggested. To comply with this approach, entire systems are modeled in the early phase of the product development. Hence, a system model of the to-be-developed system is created, which serves as the system specification to support other development activities. For this purpose, there are specific system modeling languages e.g. SysML. CATIA is a CAD-system and was originally used to design and simulate 3D-models. The functionality of the new CATIA version 6 has been extended towards MBSE. It offers a RFLP-approach for supporting the product development, which not only can design and simulate the physical models, but also model and simulate the Systems. In this paper, a system model -in terms of MBSE- is constructed with SysML for a mechatronical system "Pedelec", where the requirements, behavior, architecture and parameters as well as their relationships are modeled. Afterwards, an analysis is performed to find out how this system model can be processed with the function of CATIA version 6. Further simulation and analysis possibilities in the CATIA-system are analyzed.