A projector is provided with a correction information generator and an image information corrector described below. The correction information generator estimates a reference plane having a normal vector that is the cross product of the average of normal vectors in N regions in the result of measurement of the shape of a projection surface and a first vector corresponding to a component having the largest degree of dispersion among the N normal vectors. The correction information generator estimates an imaginary projection surface by causing the result of projection of the projection surface on the reference surface to rise upright with respect to the reference surface and generates image correction information based on the imaginary projection surface. The image information corrector generates correction image information from image information on a projection image and the correction information. The projector projects an image based on the correction image information on the projection surface.