We have designed and synthesized a new luminescent coordination polymer [Zn₂(NO₃)(NCP)₃(H₂O)₃]_n·2nH₂O (1, HNCP = 2-(2-carboxyphenyl) imidazo-[4,5-f]-1,10-phenanthroline) under hydrothermal conditions, which has been structurally characterized by single-crystal X-ray diffraction analyses. 1 crystallizes in monoclinic, space group P2₁/n, with a = 13.7748(3), b = 19.2651(4), c = 19.9543(4) Å, β = 95.339(2)º, V = 5272.35(19) ų, C₆₀H_39.73N₁₃O_13.33Zn₂, M_r = 1286.80, D_c = 1.621 g/cm³, Z = 4, μ(MoKa) = 2.118, F(000) = 2629, the final R = 0.0598 and wR = 0.1483. In 1, the organic ligand NCP^‒ displays two different bridging modes to connect adjacent Zn(II) ions into a 1D chain along the c-direction. Photoluminescent analyses reveal that 1 exhibits a strong green emission with a fluorescent lifetime of 5.57 ns. The first-principle calculation results show that the luminescence mainly originates from ligand-centered charge transition.