The structure of 1N-nitroso-2, 6-diphenylazabicyclo[3.3.1]nonan-9-one thiosemicarbazone (NDAOT), C21H23N5OS, F. W. = 393.506, orthorhombic, Pna2(1), a = 8.426(3)angstrom, b = 17.862(5)angstrom, c = 13.313(4)angstrom, V = 2003.6(1)angstrom(3), Z = 4, D-cal = 1.304 M gm(-3), mu = 0.183 mm(-1), F(000) = 832, lambda(MoKalpha) = 0.71073 angstrom, final R1 and wR2 are 0.0501 and 0. 1029, respectively. The cyclohexane and piperidine rings adopt chair-chair conformations. The phenyl rings are equatorially and bisectionally substituted at 2, 6-positions of the piperidine ring. The molecules are packed in the unit cell with the help of C-(HS)-S-..., N-(HS)-S-..., and N-(HO)-O-... types of intra- and intermolecular hydrogen bondings. An intermolecular C-H(...)pi interaction also plays a role in stabilizing the molecules in addition to van der Waals forces.