Artificial colorants are widely used because of their low prices and useful chemical properties. For example, as compared with natural food dyes, many artificial colorants are more stable to heat, light, and oxygen. This feature is advantageous in quality control of the colorants. However, it has been pointed out that their excess or combinational use may cause toxic effect. In this note, a simultaneous determination method for 18 artificial colorants using PDA (photo-diode array) detector is described.