The title compound, [Ni(HL1-NO2)2]•CH3CN, [H2L1-NO2 = 2-[2-(hydroxymethylphenyl)iminomethyl]-4-nitrophenol], was synthesized and characterized by single-crystal X-ray analysis. The compound crystallizes in the triclinic space group P1 with cell parameters a = 10.556(2)Å, b = 11.779(3)Å, c = 12.247(3)Å, α = 86.412(10)°, β = 71.135(8)°, γ = 73.009( 8)°, V = 1377.2(5)Å 3 , Dcalcd = 1.549 g/cm 3 , Z = 2. The R1 [I > 2σ(I)] and wR2 (all data) values are 0.0362 and 0.1024, respectively, for all 5989 independent reflections. The tridentate ligands coordinate to the nickel atom as a mermanner.