Two new metal–organic coordination polymer frameworks formulated as, {[Co(nta)]·H3O+}n (1), and {[Zn(ina)Cl2]·H3O+·H2O}n (2) (nta = nitriliotriacetic acid, ina = isonicotinate), have been synthesized under mild conditions and characterized by elemental analyses, IR spectrum, PXRD, thermal gravimetric analysis (TG) and single-crystal X-ray diffraction. Complex 1 crystallizes in the orthorhombic space group P2(1)2(1)2(1) with unit cell parameters a = 8.403(4) A, b = 10.165(5) A, c = 11.230 A, β = 90, V = 959.3(9) A3. Complex 2 crystallizes in the monoclinic space group P2(1)/c with unit cell parameters a = 7.1334(13) A, b = 22.369(4) A, c = 7.0089(13) A, β = 101.099(2), V = 1097.5(3) A3. In fact, 1 is a new 3D cobalt complex with the nta ligands acted as bridges to form network polymer. Each nta ligand bonds to three cobalt ions, and each cobalt ion coordinates with three nta ligands in different directions. 2 displays a new 1D zigzag chain linked by ina ligand and an interesting 1D hydrogen-bond infinite chain consists of seven-membered rings and four-membered rings. These chains are further linked to generate a new 3D framework. Two novel metal–organic coordination polymer frameworks have been synthesized under mild conditions and characterized by elemental analyses, IR spectrum, PXRD, thermal gravimetric analysis (TG) and single-crystal X-ray diffraction.