Age and growth of chub mackerel, Scomber japonicus, were studied in the Izmir Bay (Aegean Sea). A total of 520 specimens were collected during the period November 1997 to October 1998 from purse-seine boats operating in the Izmir Bay. Fork lengths ranged between 12.5 and 27.2 cm. Overall female: Male ratio was 1:1.13. Age distribution of the samples ranged from I to IV years (otolith readings). Chub mackerel grew positive allometrically (b = 3.40+/-0.05 at 95% confidence level). Growth parameters of the population were: L-infinity = 27.15 cm, K = 0.20 year(-1), t(0) = -0.48 years for females; L-8 = 29.64 cm, K = 0.23 year(-1), t(0)= -0.39 years for males and L-8 = 29.87 cm, K = 0.20 year(-1), t(0)= -0.36 years for both sexes. Growth index (Phi') was calculated as 2.29, 2.31 and 2.25, respectively for females, males and sexes combined.