The title compound, (C10H10N2)[CdBr4], was synthesized via a hydrothermal reaction. Its structure features discrete 4,4'-bipyridinium cations and tetrahedral [CdBr4]2- anions linked into ion pairs by single N-H...Br hydrogen bonds. Photoluminescent investigation reveals that the title compound displays a strong emission in the blue region, which may originate from pi --> pi* charge-transfer interactions of the 4,4'-bipyridinium cations.