Sweet potato vermicelli is also known as sweet potato vermicelli, slipknot and sweet potato vermicelli. It is an ancient traditional food of Han nationality. The main raw material is fresh sweet potato, which has the characteristics of long-term cooking, delicious fragrance and various eating methods. It is a popular and common food in most areas of China. The quality and taste are the best. In 21, Leiyang sweet potato vermicelli was rated as a trademark product of geographical indications in China by AQSIQ and SAIC.