A very stable Cd^II-organic framework, {[Cd₃(Tipe)_1.5(bpodc)₂Cl₂]·(H₂O)₂}_n (compound 1, Tipe = 1,1,2,2-tetrakis(4-(imidazol-1-yl)phenyl)ethene, bpodc = benzophenone-4,4-dicarboxylic acid), has been successfully synthesized under hydrothermal conditions. Compound 1 crystallizes in the triclinic system, space group P, with a = 12.289(3), b = 15.951(4), c = 20.755(5) Å, α = 81.248(2)°, β = 83.905(2)°, γ = 89.452(2)°, V = 3998.2(17) ų, Z = 2, M_r = 1839.59, D_c = 1.528 g/cm³, μ = 0.925 mm^-1, F(000) = 1844, R = 0.0508 and wR = 0.1571 for 13998 observed reflections (I > 2σ(I)). Its overall structure is a three-dimensional stacking with a porosity of 10.1% based on a calculation by PLATON. Compound 1 shows a blue fluorescence emission with the peak maximum of 501 nm (λ_ex = 397 nm) by ligand-to-ligand charge transfer of TPE chromophore. And it exhibits excellent performance in detecting Fe³⁺ and Cr₂O₇^2- ions in aqueous solutions as a multi-response sensor.