In the centrosymmetric title complex, [Ni(C7H7N4O3)(2)- (C-5 H5N)(2)], the coordination geometry about the Ni2+ ion is octahedral, with two deprotonated 1-methyl-3-(p-nitrophenyl)triazenide 1-oxide ions, viz. [O2NC6H4NNN(O)CH3](-), acting as bidentate ligands (four-electron donors). Two neutral pyridine (py) molecules complete the coordination sphere in positions trans to each other. The triazenide 1-oxide ligand is almost planar, the largest interplanar angle of 8.80 (12)degrees being between the phenyl ring of the p-nitrophenyl group and the plane defined by the N3O moiety. The Ni-N-triazenide, Ni-O and Ni-N-py distances are 2.0794 (16), 2.0427 (13) and 2.1652 (18) Angstrom, respectively.