The curing process of composite parts leads to undesired deformations and the composite part does not meet the industrial requirements. The curing process has several parameters which can be tuned to reduce these deformations. One of these parameters is the geometry of the mold which can be changed to eliminate the curing deformations. The subject of this paper focuses on this process which is called mold compensation. It presents a method to adapt the shape of the mold using a reduced spectral basis in order to eliminate the curing deformations. The spectral basis is spanned by the eigenfunctions of Laplace-Beltrami operator applied to a skeleton mesh of the composite part. The curing deformations are also expressed in this basis. The advantage of the proposed method is that it can easily parametrize the shape of the composite part without the need of parametrizing the nominal curing finite element model. The mold compensation problem is formulated as solving a system of nonlinear equations. Using the proposed parametrization, the fixed-point and the Broyden methods are tested to solve this system of non-linear equations. Two numerical test cases are presented to show the efficiency of the proposed method.