Although chub mackerel (Scomberjaponicus) is a primary pelagic fish species,we have only limited knowledge on itskey life history processes.The present work studied the age and growth of chub mackerel in the East China and Yellow Seas.Agewas determined by interpreting and counting growth rings on the sagitta otoliths of 252 adult fish caught by the Chinese commercialpurse seine fleet during the period from November 2006 to January 2007 and 150 juveniles from bottom trawl surveys on the spawn-ing ground in May 2006.The difference between the assumed birth date of 1 st April and date of capture was used to adjust the agedetermined from counting the number of complete translucent rings.The parameters of three commonly used growth models,the vonBertalanffy,Logistic and Gompertz models,were estimated using the maximum likelihood method.Based on the Akaike InformationCriterion (AIC),the von Bertalanffy growth model was found to be the most appropriate model.The size-at-age and size-at-maturityvalues were also found to decrease greatly compared with the results achieved in the 1950s,which was caused by heavy exploitationover the last few decades.