A novel, fast and accurate separation-preconcentration method for supramolecular liquid phase microextraction of sudan orange G dyestuff prior to its UV-vis spectrophotometric determination was developed. Sudan orange G in the model solution was extracted to the supramolecular solvent phase at pH 4.0. Supramolecular solvent used in this study was prepared from tetrahydrofuran (THF) and decanoic acid. Sudan orange G concentration was measured in the UV-Vis spectrophotometer at 380 nm. The sample volume, pH, matrix effect, centrifugation time, ultrasonic bath time, supramolecular solvent volume has been optimised and the work was done under these conditions. The relative standard deviation % value was found below 5%. In this study, the limit of detection (LOD) value and preconcentration factor were found to be 3.4 mu gL(-1) and 40, respectively. The presented supramolecular liquid phase microextraction procedure was applied to artificial sweat samples and water samples.