ta-siRNA is a class of 21 nt endogenous non-coding small RNA.Its regulatory cascades have been identified as important elements in gene networks involved in the plant phase transition of juvenile-to-adult,development of adaxial-abaxial leaf/flower,and response to biotic and abiotic stresses,and DNA methylation at the TAS locus.In this paper,we reviewed the advances of ta-siRNA regulatory cascades,including its discovery,function,types and identification,and also discussed its present problems and furture research prospects.We hope the review could provide a useful reference for ta-siRNA research and utilization.