Under solvothermal conditions, a new Cu(I) coordination polymer ［Cu(H2O)(MIBA)］n was synthesized by using semi-rigid imidazole carboxylic acid ligand 4-(2-methylimidazole) benzoic acid and copper, in which MIBA is the negative monovalent anionic coordination polymer of 4-(2-methylimidazole) benzoic acid. The solid-state fluorescence properties of Cu(I) organic skeleton coordination polymer based on semi-rigid imidazole carboxylic acid ligands were studied at room temperature. The maximum emission peak of MIBA ligand is 433 nm, and the maximum emission peak of coordination polymer ［Cu(H2O)(MIBA)］n is 412 nm, all of which show fluorescence properties. In addition, its crystal structure was characterized by X-ray single crystal diffractometer, infrared spectrum, thermogravimetric analysis and elemental analysis. X-ray single crystal diffraction shows that the polymer is a 3D→3D double interpenetrating network with a (64·82) four-connected single-node topology.