Abstract: Using 2,5-dimethoxyterephthalic acid (H₂DTA) as organic ligand and imidazole derivative 1,1′-(2-methyl-1,4-phenylene)bis(4-methyl-1H-imidazole) (MPBMI) as auxiliary ligand, a metal organic framework material Cd₂(DTA)₂(MPBMI)_1.5(H₂O)_n (MOF 1 ) with fluorescent properties was successfully constructed by solvothermal method. Single crystal X-ray diffraction analysis shows that the material has a three-dimensional skeleton and can be simplified into a 4,6-connected network topology. Good solid fluorescence emission and fluorescence test results of common anions in aqueous phase show that MOF 1 has good fluorescence and can realize highly selective fluorescence quenching detection of Cr₂O₇²⁻ anions in aqueous solution.