The title compound, (C(5)H(7)N(2))(2)[CdI(4)]·H(2)O, contains one [CdI(4)](2-) anion, two prontonated 4-amino-pyridine mol-ecules and one water mol-ecule in the asymmetric unit. In the anion, the Cd(II) atom is coordinated by four I atoms in a slightly distorted tetra-hedral geometry. The [CdI(4)](2-) anion and the water mol-ecule are bis-ected by a crystallographic mirror plane perpendicular to the c-axis direction, with the Cd(II) atom, two of the I atoms and the atoms of the water mol-ecule located on this plane. The crystal packing is stabilized by inter-molecular N-H⋯I, N-H⋯O and O-H⋯I hydrogen bonds and by π-π stacking inter-actions [centroid-centroid distance = 3.798 (3) Å) between pyridine rings, which build up a three-dimensional network.