The measurement of deformation and force for microcantilevers is an important issue in microassembly. An optical method based on local feature point matching and the digital image correlation (DIC) for deformation and force measurement of microcantilevers is proposed. Images of a microcantilever before and after deformation are obtained by an optical microscope. Using the Laplace-of-Gaussian (LOG) operator, feature points with local extreme response values are detected in the scale space in images before and after deformation. For each LOG feature point, an affine-invariant closed region is extracted based on which the sub-pixel position of the LOG point is relocated as the center of gravity of the closed region and an affine-invariant feature descriptor is constructed. Corresponding points in images before and after deformation are matched according to their affine invariant descriptors. To obtain the displacement of feature points with a higher resolution in bending deformation, the digital image correlation algorithm with a third-order transformation function is used and initialized by the sub-pixel information of matched points. The deformation of the microcantilever can be calculated by fitting the displacement of the matching points with the beam's bending deflection formula under the plane stress condition. Then, the force values as well as the position where the loader comes in contact with the cantilever are calculated through the least-squares method. The validity of the proposed method is verified through experiments on actual microcantilever deformation and comparison with other methods.