An investigation of the interaction of Bi(III) with an aqueous solution of sulfanilic acid at a higher temperature is performed. As a result, a new composition [Bi6O6(OH)(2)](NH2C6H4SO3)(4) is precipitated. This Bi(III) complex is characterized by various methods: elemental analysis, DTA, TG- MS, DSC, FTIR, and powder X-ray diffraction. Based on the experimental results, X-ray diffraction indexation as well as thermal decomposition products of the compound are suggested. (C) 2011 Elsevier B.V. All rights reserved.