Sea cucumber belongs to Echinoderm of Holothurian class, which grows on the fine sand seabed and rock bottom rich in algae. In the past, sea cucumber mainly relied on artificial diving to find and catch, which was labor-consuming and time-consuming, with less catch and high cost. In addition, sea cucumber was delicious and nutritious, so it has always been a valuable seafood.

There are many varieties of sea cucumber, and the common ones in the market are Stichopus japonicus, Plum Blossom Ginseng, Dawu Ginseng, Topaz Ginseng, Square Stichopus japonicus, Baishi Ginseng and Keshen Ginseng.

Stichopus japonicus, also known as grey ginseng, is mainly produced in northern China. 500 grams of dry goods can be soaked in water for 3500 ~ 4000 grams, with thin skin and fine meat, many thorns, beautiful appearance and excellent flavor. The Japanese ginseng produced in Hainan Island has the reputation of "the king of sea cucumbers", with the largest length of 1.2 meters, large body and thick flesh, many sharp thorns and slightly inferior flavor to Japanese ginseng. Some sea cucumbers are smooth and spineless, such as white stone ginseng and gram ginseng. Some are shaped like vases, such as vases and ginseng.