The new organic inorganic compound [C 8 H 10 NO] 2 CdCl 4 crystallizes at room temperature in the orthorhombic system (CmCa space group) with the following unit cell parameters: a=19.9803(5)Å, b=15.3829(3)Å, c=13.8168(3)Å and Z=8. The atomic arrangement can be described as an alternation of organic/inorganic layers along the a direction. The organic layer is built up by one type of [C 8 H 10 NO] + cation and the inorganic layer is built up by isolated and distorted tetrahedral CdCl 4 2− anions. The TGA–DTA curves revealed two endothermic peaks. The first peak may be due to a phase transition, while the second peak corresponds to the decomposition point. Additionally analysis of the dielectric constants ε′ and ε″ versus temperature at several frequencies shows a relaxation process which could be due to disorder in the lattice.