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A total of 524 (328 males, 196 females) blue sharks were sampled from tuna long line fishery survey in the northwest Atlantic Ocean(48° to 52°N/15° to 34°W , 3° to 15°N/34° to 40°W) from October 2010 to March 2011.Whole vertebrae of 51 males (104~254cmFL) and 52 females(135~211cmFL) were analyzed.The results showed that the relationship between fork length (FL) and vertebral radius (VR) for both sexes was as follows: FL=194.96VR0.8603(n=9l, R2=0.9098).Estimating the vertebral growth rings used 10% cobalt nitrate.Males were aged to 9 years (256cmFL)and females were 7years (211cmFL).The index of average percentage error (IAPE) ranged from0~6.33% for 2~9years.Parameters derived from observed length-at-age for males and back-calculated lengths for females were best to describe the growth of the blue shark, respectively.Von Bertalanffy1m =335.00cmFL, k =0.14yr-1,t0 =-0.54yr for males and growth parameters were1m =291.5cmFL k =0.14yr-1, to =-0.70yr for females.The longevity for males and females was20years and 21years, respectively.