Abstract  Organisms utilize chemical signals to perceive their external environmental and regulate their behavior and development. The discovery of ascarosides; a class of small molecular compounds, has been a breakthrough in the study of nematode pheromones. Ascarosides are structurally and functionally diverse and occur widely in nematodes. They regulate a variety of behaviors, including mating, diapause, foraging, aggregation, and dispersal. This paper primarily summarizes the structure, function, biosynthesis, metabolism and signal transmission of ascarosides, thereby providing a reference for future research on chemical signal regulation theory, multi-species interactions, and the development of novel targeted drugs.