According to Baidu Aigou, leech is a common medical raw material, which has the functions of anticoagulation, anti-inflammation, detoxification, expelling wind and relieving pain, and is widely used in clinical medicine, health care products, beauty care and other fields. The commonly used leeches in the market mainly include medicinal leeches and cultured leeches. Leeches need to be dried for storage and use in pharmaceutical processes. Different kinds and qualities of leeches have different drying speeds. Generally speaking, it takes 8- 10 kg to dry leeches into one kilogram.