Sweet potato vermicelli is also known as sweet potato vermicelli, slipknot and sweet potato vermicelli. It is an ancient traditional Han food. The main raw material is fresh sweet potato, which has the characteristics of not rotten after being cooked for a long time, fragrant and delicious, and can be eaten in various ways. It is a favorite and common food in most parts of China. The quality and taste are the best. In 2010, Leiyang sweet potato vermicelli was rated as a Chinese geographical indication trademark product by the General Administration of Quality Supervision, Inspection and Quarantine and the State Administration for Industry and Commerce.