The roles of nitric oxide (NO),a significant gas signaling molecule,in regulating plant physiology progress and modulating signal transduction is being a novel hotspot of researches.In recent decades,a great deal of important progress have been achieved on the roles of NO in the generation and development of plant root,especially on the generation of endogenous NO from plant roots,the details of NO-participated progress of root generation and development,and the related signaling pathways.In order to get further understanding of the roles of NO in plants,the update advances in studying the generation of endogenous NO in plant root and the mechanisms and signaling pathways of NO in promoting generation and development of plant root are reviewed.