In this work a practical electrochemical approach has been developed by using gold (Au)-film electrode for phenytoin detection. The formation of Au-film was monitored by using scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy techniques. After the electrochemical characterization, the experimental conditions were optimized and then the analytical characterizations were examined. As a result, two linear ranges were found between 5x10 À 7 M and 2x10 À 4 M with the limit of detection and limit of quantification values as 0.302 μM and 1.013 μM respectively. The developed system was applied for phenytoin detection in synthetically prepared plasma solution and as a result recovery value of 99.5% � 0.056 was obtained.[a] T.