In the anion of the title salt, C10H16N(+)·C10H4ClN4O7(-) [trivial name = N,N-diethyl-anilinium 5-(3-chloro-4,6,-dinitro-phen-yl)barbiturate], the dihedral angle between the benzene and pyrimidine rings is 45.49 (6)°. The mean plane of the nitro group, which is ortho-substituted with respect to the pyrimidine ring, is twisted by 41.57 (13)° from the benzene ring, while the mean plane of the nitro group, which is para-substituted, is twisted by 14.41 (12)° from this ring. In the crystal, N-H⋯O hydrogen bonds link cations and anions into chains along [1-10]. Within the chains, inversion-related anionic barbiturate anions form R2(2)(8) ring motifs.