Rebuilding of CAD model from deformed mesh important displacement case. Nowadays, we attend a development of work in project mode which is characterized by the mobilization of multiple competences. The globalisation of the markets as well as the reduction in costs and in delays for developing new products led to the development of collaborative working tools in a distant way ensuring the structuring, the follow-up, and the traceability of the exchanges. That induced a considerable increase in the needs of inter-applications communication and total coherence of the support systems of the various product models (CAD, analysis, CAM). Besides their strong interdependences, both CAD and calculation activities will be built on new emergent technologies in the fields of the data modeling (model of product) and of the processes (interoperability) in order to be able to take into account the handling of heterogeneous objects (geometry, meshing, deformation, etc.). Indeed, in a context of collaborative work, the numerical integration of these two activities: CAD and calculation became one of the main concerns in CAD/CAM. The required objective here is to promote sharing the data without manual transformations in order to improve the flow of information between CAD and calculation while guaranteeing the reliability and the traceability of the data. Our research is oriented to CAD/CAM/analysis integration by rebuilding the CAD model starting from the FE results (deformed mesh). This paper presents techniques for rebuilding the geometrical and topological entities of the CAD model starting from a deformed mesh. [ABSTRACT FROM AUTHOR]