This paper deals with an approach to identify geometrical deviations of flexible parts from optical measurements. Each step of the approach defines a specific issue which we try to respond to. The problem of measurement uncertainties is solved using an original filtering method, which permits to only consider a few number of points. These points are registered on a mesh of the CAD model of the constrained geometry. The shape resulting from deflection can be identified through the finite-element simulation of the part’s deformation due to its own weight and the measuring set-up. Finally, geometrical deviations are obtained by subtracting geometrical deflections to measured geometrical deviations. The method is illustrated in an experimental test case.