Abstract: Objective To review the current taxonomy, morphology, physiological adaptation mechanisms and pharmacological effects of leeches as well as research progress in repellency and control measures in order to provide a reference for basic research, development of pharmaceuticals, and efficient use of leech resources. Methods Such databases as CNKI, Wanfang Medicine, PubMed, Web of Science, and the China Species Library were searched for related literature. Studies on the taxonomy, anatomy, physiology, pharmacology, and control technologies of leeches were summarized and analyzed. Results The taxonomic system of leeches was not made uniform in China, and the actual species of leeches might have been underestimated. Leeches possessed a specialized morphology, anatomy, and mechanism for physiological adaptation, whose salivary gland secretions were rich in bioactive components and important pharmacologically due to their anticoagulant, antithrombotic, anti-inflammatory, and wound-healing-promoting properties. However, the mechanisms of action and structure-activity relationships remained to be elucidated. Despite the constant advances in research on repellency, control, and resource utilization of leeches, the related technological systems still needed to be improved. Conclusion Considerable progress has been made in research on the taxonomy, morphological structure, and pharmacological effects of leeches. However, the taxonomic revision, diversity surveys, and development and application of active components leave much to be desired. Traditional taxonomy should be used in combination with molecular systematics. More effort needs to be devoted to the functional analysis, applications and development of pharmacologically active substances derived from leeches so as to promote the valid evaluation, rational use, and sustainable development of leech resources.

Key words: Leech, Taxonomy, Morphology, Physiology, Pharmacology, Control, Repellence