Traditional medicine is one of the oldest therapies in human societies, which has been used by different nations, and its development is indebted to tradition, culture and customs of different nations. Traditional medicine still retains its place in many countries alongside modern medicine to maintain health and treat diseases and has progressed considerably.

Traditional medicine is a holistic approach to health, knowledge and skills, with a plethora of ways to maintain health and treat various diseases and has a direct relationship with plants, animals, minerals and manual procedures. One of the techniques used in traditional medicine is leech therapy. Leech has been labeled a tiny surgeon. Therefore, we referred to traditional medicine texts and gathered comments of philosophers and doctors of traditional medicine in Iran regarding the use of leeches in the treatment of various diseases. In this paper, we made an attempt to discuss treatment modalities in Iranian traditional medicine