In the title Schiff base compound, C(12)H(15)N(3)O(2), obtained from a condensation reaction of cyclo-hexa-none and 2-nitro-phenyl-hydrazine, the phenyl-hydrazone group is planar, the largest deviation from the mean plane being 0.0252 (12) Å, and the nitro fragment is twisted slightly with respect to the mean plane, making a dihedral angle of 6.96 (17)°. The cyclo-heaxanone ring displays a chair conformation. An intra-molecular N-H⋯O hydrogen bond helps to stabilize the mol-ecular structure.