Abstract: In order to establish a detection method of buckwheat powder adulteration,chromatographic fingerprint of Ultra High Performance Liquid Chromatography( UPLC) method was used.Rutin as reference peak,according to relative peak area of the characteristic peak,simulated buckwheat powder samples adulterated respectively with barley powder or wheat flour were identified by System Clustering Analysis method. The results showed that buckwheat powder,which was adulterated with more than 2% barley powder or wheat flour,could be identified.The buckwheat powder from the market and the pure buckwheat powder could be clearly distinguished by clustering analysis method.The method was simple,high sensitivity and good stability,good repeatability,detection could be used to incorporate the identification of flavonoid- free barley,wheat and other samples.