The invention provides a rapid and selective detection method of baicalein. A traditional Chinese medicine material or Chinese patent medicine preparation is crushed into powder, stirring extraction is performed with absolute ethyl alcohol for 12 h, and a test solution is obtained after filtration and volume metering. A configured beta-CD-Pd-GR/GCE nano-composite modified electrode electrochemical sensor is used for detecting and analyzing the test solution to determine the content of the baicalein. A preparation method of the electrochemical sensor for the baicalein is low in preparation cost, simple in technology and easy to operate, the electrochemical sensor prepared with the method can be used for detecting the baicalein successfully and is high in sensitivity and good in stability.