This paper introduces a method for the recognition planar objects under projective geometry. Our method is based on a similarity measure invariant to projective transform. The proposed similarity measure utilizes the distribution of the projective relations between the conic section pairs, which are estimated from the object's shape. We conjecture that given two objects of the same type, which are viewed from different viewpoints generate similar histograms, such that their difference is smaller than the histograms generated from other object types. The proposed measure has shown promising performance on the Brown shape database.