A novel manganese complex, C16H26MnN4O12, was synthesized by the reaction of nicotinoyl-glycine and NaOH in an ethanol/water solution and structurally characterized by elemental analysis, UV-vis spectrum, IR spectrum and single-crystal X-ray diffraction analysis. The crystal of the complex belongs to the triclinic space group P1 with a = 7.8192(16) Å, b = 8.8800(18) Å, c = 9.0142(18) Å, α = 83.14(3)°, β = 65.27(3)°, γ = 81.67(3)°, V = 516.3(2) Å3, Z = 1, Dx = 1.542 mg·m−3, μ = 0.66 mm−1, F(000) = 271, and final R1 = 0.0381, ωR2 = 0.0964. The nicotinoyl-glycine ligand acts as a bridging ligand to connect the manganese ions by the hydrogen interactions; thus, the complex expands into a 3D supramolecular net structure.