The present invention relates to a linear inorganic coordination polymer and a metal complex compound which are prepared in the form of a metal nanostructure having various stereo structures and thus can be used as a catalyst or the like having an excellent activity in preparing a polyalkylene carbonate resin and the like, and a metal nanostructure and a catalyst composition comprising the same. The linear inorganic coordination polymer comprises a repeating unit having a form in which a predetermined oxalic acid derivative is coordinately bonded to a transition metal, and the metal complex compound comprises a plurality of linear inorganic coordination polymer chains and has a structure in which the plurality of polymer chains are linked to each other via a predetermined neutral ligand.