Cationic dye clay modified electrodes and anionic dye clay modified electrodes showed different electrochemical behavior. Catonic dye clay modified electrodes prepared by a one step method did not exhibit voltammetric response while the anionic dye clay modified electrodes did. X-ray diffraction and spectrophotometric experiments suggested that most of the cationic dye adsorbed in interlamellar space charged negatively and strongly interacted with the clay. However, anionic dye did not enter the interlamellar space due to electrostatic repulsion and had no strong interaction with the clay.