Abstract: The recognization of the shapes of buildings,annotation and so on,is commonly based on grid data,whose research base point is pixel.The shortcomings of it lie in low precision and large calculations.A brand-new research thinking is put forward,which uses vector as research base point instead of grid(pixel) and designs recognization algorithm based upon vector.Polygonal inquiry based on shape template match is designed under such thinking.Inquiry operator in the method is Fourier descriptor.The experimental results show that inquiry operator using the new Fourier descriptor to calculate has high differentiation degrees and good query results,which is really a steady and highly effective recognization tool.