Abstract: Salicylic acid (SA) and jasmonic acid (JA) are kinds of growth regulation substances with ubiquitous distribution among plants. It has been shown that both SA and JA are in wounding signal transduction pathways. It has been suggested that cytokinins and small GTP_binding proteins might be the switch of JA and SA signal ing pathways. Advances have been made in the study of the relationships between JA- and SA-signal transduction pathway. SA or ASP (Aspirin) prevents wound_induced gene expression by blocking JA biosynthesis; JA inhibits pathogen_induced accumulation of SA.