Choy Sum originated in southern China. It is a long-term selection, cultivation and domestication of cabbage easy bolting materials, and has formed different types and varieties. Mainly distributed in Guangdong, Guangxi, Taiwan, Hong Kong, Macau and other places. In the latter part of the 20th century, Japan was successfully introduced. Choy Sum is a specialty vegetable of Guangdong, China. It has soft quality and delicious flavor, and can be cultivated on an annual basis. Therefore, it is a large-scale vegetable in Guangdong and Guangxi. It is sold to Hong Kong and Macau on an annual basis and has become the main export vegetable. A small amount is exported to Europe and the United States, regarded as precious vegetables.