Abstract: In order to determine amylose，amylopectin content of Tiegun yam，Chenji yam，Nanyang yam，Foshou yam，Huai yam and Xiaobaizui yam，and contrast variety difference，acid hydrolysis method was used to determine the content of starch，content of amylose and amylopectin was determined by UV spectrophotometer.Each yam was tested for 10 roots，and the average value was determined.Test results showed that fresh yam had higher amylose and amylopectin content，and it was a kind of twining vine with higher starch content.Starch content，amylose content and amylopectin content of different varieties of yam were different.Stability of the content in the same variety was better，but stability of different varieties also has some differences，which could be used as basis for quality identification and variety identification.