1. An object pose estimating and matching system comprising: reference three-dimensional object model storage means for storing, in advance, reference three-dimensional object models of objects; reference three-dimensional weighting coefficient storage means for storing, in advance, reference three-dimensional weighting coefficients corresponding to said reference three-dimensional object models; pose candidate determining means for determining pose candidates for an object; comparative image generating means for generating comparative images close to an input image depending on said pose candidates, based on said reference three-dimensional object models; weighting coefficient converting means for converting said reference three-dimensional weighting coefficients into two-dimensional weighting coefficients depending on said pose candidates, using said reference three-dimensional object models; and weighted matching and pose selecting means for calculating weighted distance values or similarity degrees between said input image and said comparative images, using said two-dimensional weighting coefficients, and selecting one of the comparative images whose distance value up to said object is the smallest or whose similarity degree with respect to said object is the greatest, thereby to estimate and match the pose of said object.